This is one of those things that depends too much on the individual or bike to say that "all adults do this" and "only children do that." Bottom bracket height varies among road bikes, necessitating different saddle heights for proper fit.

At least for me, I can scrape the toe of a shoe while coasting, but have to lean too far to the side to be stable if I want to rest on one toe and my saddle. Good thing I don't have to impress anyone, 'cause I'm not changing how I do things.