I guess my feelings about the "worth" of meeting the characters is skewing my perspective over why an adult would want to "waste" time standing in line meeting them. I wasn't asking because I didn't think it was an adult's right to do so; I was asking because I guess I don't see the value in that vs going on a ride or other attraction. I guess I put the characters below rides and shows if I were to rank them in order of importance. I do it because my kids like it, but I do draw the line somewhere. We only have so much time in the parks each day with ADRs and younger kids who can't stay out late. If we get to the park early in the day, we can stand in line for an hour or more to meet Rapunzel or we can use that time to go on 4 or more rides. To me, the choice is obvious. My kids decided not to see Rapunzel since that would have been the only thing we could have done on our last morning there. We told them we could stand in the Rapunzel line (it was only about 12 kids/families deep at that point, but it was 40 minutes from the time she was even coming out) or we could go on some final rides before we went shopping and left. They both decided to ride some rides and forgo Rapunzel. (Honestly, I think it's ridiculous that Disney has ONE place in all of Disney that people can meet her; thus creating this long wait issue on their own, but that's a whole different post.)
In my mind, I think that I paid so much to get down to Disney, stay there, and get park tickets, that if I stand in line to have my picture taken with, say, 10 characters, and that took an aggregate of 5 hours, those 5 hours could have been spent on other things. Obviously, many do not share my feelings and that is ok.