My first child has always been a slave to routine and familiarity. He's much more willing to try new things than he used to be, but with something like, say, peeing on the potty, I would worry that he might have to go outside the house and just not be willing to use a strange toilet. It took a long time before he would even use the toilet at school.
My daughter, however, once she likes doing something, wants to try all the different variations. She would love to try every toilet. Last week she told me she had to pee while we were in the car. I had told her when we were getting in that I had a little portable potty in the car, so she should always tell me when she has to go, even if we're in the car. We stopped at a rest stop and I offered to take her in. No, she wanted to use the portable potty. But nothing came out. So we tried the potty inside the rest stop. Still nothing. (She just wanted to try them out.) Once at the mall, she tried at least two toilets (successfully.) She loves to go at school and will even request that her teacher help her with wiping rather than me, even if I'm there. And best of all, the other day we were coming home from the Boston Aquarium with friends in the car, stuck in traffic on Rt. 2, and she said she had to pee. "Can you hold it for a little while, or do you have to go now?" I asked. "I have to go now." So I pulled over at a gas station just off Rt. 2. Ooof! The smell hit hard from the one bathroom (no separate women's.) The nasty looking bar of soap sat on a sponge on the sink. "Ok, Sierra, don't touch anything. You're going to go quickly, and we'll wash our hands with wipes at the car." She was so proud of herself, using the gas station bathroom and staying dry!