I have to agree pretty much with your thinking, Bob.
Butt Dude, the asshole just got bigger and bigger! There's casual observance of body parts, butt then there's a rectal exam! I'm pretty sure that you won't be selling much advertising space.
Jbee 
So am I confronting a taboo head on, or turning my back on the taboo? When a person goes to one of these trailheads, the only building there is the toilet, and that is a solidly built concrete structure. The other things to see other than the parking lot is a sign. The expensive and solidly built toilet building is obviously the most important feature there. Its also taboo to talk about and taking photos is frowned upon.
Being the only building implies that using the toilet building is the most important human activity at these trailheads. Peeing is an activity that all humans engage in several times every day. Pooing is not as common but all healthy humans do that about once every day. Humans also always feel better after having done so. We aren't supposed to talk about it, and never take pictures of those parts of your body. Facebook abounds with pictures of food being eaten, but a photo of the other end of the normal body process, or even the body parts that perform the other end of the process will get you kicked off of Facebook.
Meanwhile, the toilet building is the most important feature at every state park because every person wants to use its unseen and unmentionable facilities with his unmentionable and unseen body process several times every day. My web photo site picture of the anus is about life size, washed and clean. Unusual to see such a photo because its so taboo. That's why its there, to confront taboos.
As for photos of the toilet buildings at trailheads, that's really an interesting (to me) study in architecture. The amount of energy and concern a culture devotes to its toilets is a measure of how much they respect their bodies and themselves. One of the first toilet buildings I actually noticed was at a US Forest Service camp at Prince Creek on Lake Chelan in Washington State, USA. Prince Creek is about 10 miles by boat from the nearest road. I was there at about age 17 or so. Their toilet building was a proverbial "stone outhouse." The walls were foot thick stone. It had two sides, male and female, and each side was a "2 holer," set up for two men and/or two women to take a dump side by side. It had no running water, just a pit underneath. I was amazed at the amount of time and labor which had gone into creating the large stone building so far from anything. In those days they probably got a total of 5 or 6 visitors per month and only in summer. I was amazed to see it there.
Other places are poorly built shacks or filthy little hidden rooms. One can tell a lot about how much people care about themselves (and their customers) by the care they take in providing for human bodies.
Since the advent of digital cameras, with free pictures, I've started including pictures of the toilet building in my hiking photo collection. Along with the parking space and sign board, it is the most prominent feature at most every established public trailhead. They are often unique, different from all the rest, a unique signature of that one trailhead, an architectural feature reflecting the culture that built them and its priorities.
I didn't include pictures of the toilet building in this trip report, just the sign boards. The sign board is the other thing one can photograph at each trailhead parking space. I see that the toilet building got into JB's linked trip report about camping at Arivaipa Canyon, although when photographed the building is being used as shade by cows rather than human occupants.
My photo web page provides a quick exit link "Get me out of here" for those who are offended by the taboo pictures.
Bob
