Tom Wolfe wrote The Electric Kool-Aid Acid Test in 1968. It was a "non-fiction novel" describing Ken Kesey, author of One Flew Over The Cuckoo's Nest and other works, and his Merry Pranksters, a group of friends who lived communally and experimented with and promoted the use of psychedelic drugs.
They purchased a 1939 International Harvester bus in 1964, stripped it down, remodeled it inside, gave it a psychedelic paint job outside, and named it "Furthur". They then went on an expedition from California to New York and back.
Along the way, as Wolfe described about two-thirds of the way through Chapter 6, "The Bus":
They have to pull into gasoline stations to go to the bathroom, cop a urination or an egestion  — keep regular friends — but 12 — how many, 14? — did we lose somebody — did we pick up somebody — climbing out of this bus, which is weird-looking for a start, but all these weird people are too much, clambering out — the service station attendant and his Number One Boy stare at this — Negro music is blaring out of the speakers and these weird people clamber out, half of them in costume, lurid shirts with red and white stripes, some of them with weird paint on their faces, like comic-book Indians, with huge circles under their eyes, etes red, noses not blue, not nearly blue enough, but eyes red — all trooping out toward the Clean Rest Rooms, already queueing up, practically —
"Wait a minute", the guy says. "What do you think you're doing?"
"Fill 'er up!" says Kesey, very soft and pleasant.
"I mean what are they doing?"
"Them? I 'spect they're going to the bathroom. Ay-yup, that big old thing's the worst gas-eater you ever saw" — all the time motioning to Hagen to go get the movie camera and the microphone.
"Well, can't all those people use the bathrooms."
"All they want to do is go to the bathroom" — and now Kesey takes the microphone and Hagen starts shooting the film — whirrrrrrrrrrrrrrr — but all very casual as if, well, sure, don't you record it all, every last morsel of friendly confrontation whenever you stop on the great American highway to cop a urination or two? or a dozen?
"Well, now, listen! You ain't using the bathrooms! You hear me, now! You see that motel back there? I own that motel, too, and we got one septic tank here, for here and there, and you're not gonna overflow it for me. Now git that thing out of my face!"
— Kesey has the microphone in the guy's face, like this is all for the six o'clock news, and then he brings the microphone back to his fact, just like the TV interview shows, and says,
"You see that bus out there? Every time we stop to fill 'er up we have to lay a whole lot of money on somebody, and we'd like it to be you, on account of your hospitality."
"It's an unaccountable adventure in consumer spending", says Babbs.
"Get those cameras and microphones out of here", the guy says. "I'm not afraid of you!"
"I should hope not", says Kesey, still talking soft and down-home. "All that money that big baby's gonna drink up. Whew!"
Sheerooooooo — all this time the toilets are flushing, this side and that side and the noise of it roars and gurgles right through the cinder block walls until it sounds like there's nothing in the whole wide open U.S. of A. except for Clean Rest Room toilets and Day-Glo crazies and cameras and microphones from out of nowhere, and the guy just caves in under it. He can't fit it into his movie of Doughty American Entrepreneur — not no kind of way —
"Well, they better make it fast or there's going to be trouble around here."
Well, that was in 1968. Gas stations now routinely sell soft drinks in sizes from 32 to 64 fluid ounces (0.95 to 1.9 liters) and rampant urination is accepted and expected.
Below are the partly functional urinals and toilet at McClure's truck stop along Interstate highway I-65 outside Lebanon, Indiana, between Indianapolis and Chicago.
The above takes place six chapters in, after Kesey has become a sort of Pied Piper to the acid movement. What was the earlier situation?
The following lavatorial passage is the second paragraph of Chapter 2, "The Bladder Totem", describing the situation at the Warehouse, where the Merry Pranksters were staying before effectively moving in with Kesey:
The bathroom; yes. There was no plumbing in the Warehouse, not even any cold water. You could go out into a little vacant lot next door, behind a board fence, and take a stance amid the great fluffy fumes of human piss that were already lufting up from the mud, or you could climb a ladder through a trap door that led up to the old hotel where there were dead flophouse halls lined with rooms of a kind of spongy scabid old wood that broke apart under your glance and started crawling, vermin, molting underlife. It was too rank even for the Pranksters. Most of them went up to the Shell station on the corner. So I went up to the Shell station on the corner, at Sixth and Howard.  I asked where the bathroom is and the guy gives me The Look — the rotten look of O.K., you're not even buying gas but you want to use the bathroom — and finally he points inside the office to the tin can. The key to the bathroom is chained to a big empty Shell oil can. I pick it up and walk out of the office part, out onto the concrete apron, where the Credit Card elite are tanking up and stretching their legs and tweezing their undershorts out of the aging waxy folds of their scrota, and I am out there carrying a Shell oil can in both hands like a bladder totem, around the corner, to the toilet, and — all right, so what. But it suddenly hits me that for the Pranksters this is permanent. This is the way they live. Men, women, boys, girls, most from middle-class upbringings, men and women and boys and girls and children and babies, this is the way they have been living for months, for years, some of them, across America and back, sailing like gypsies along the Servicenter fringes, copping urinations, fencing with rotten looks — it even turns out they have films and tapes of their duels with service-station managers in the American heartland trying to keep their concrete bathrooms and empty Dispensa-Towels safe from the Day-Glo crazies. . .
Also see my pictures of The Urinal of Hunter S Thompson, another practitioner of the New Journalism, who mentions Wolfe and Kesey in his book Hell's Angels and who is mentioned by Wolfe in The Electric Kool-Aid Acid Test.
And seriously, go read some Tom Wolfe!