Your Best bet....
Try going to the corporate website and e-mail them and ask if they allow it. It wasn't illegal a few years ago when I worked at Wal-mart in Indiana, but I can't guarantee that it's legal anywhere else.
Wouldn't suggest doing the one-hour thing, because they might have a rule against it that could cause you hassles. (Some of these places have their machines situated so that nosy customers can see the photos coming out.)
You might want to check into getting someplace like one of the online developers to do it. Snapfish or something.
Please remember I'm not an attorney, nor do I play one on t.v. I'm just an ordinary person who can't resist putting their two cents' worth in!