DH & I aren't big on getting our pictures taken with characters. That said, we went over and had our picture taken with Pluto. When we saw the pictures, there was no way I wanted it. (I don't usually wear a cap, was wearing my fanny pack - didn't look very good!)
When we were in ToonTown, we walked thru Mickey's House and ended up getting our picture taken with Sorcerer Mickey (my favorite Mickey!) I remembered to take off my fanny pack & cap and we ended up getting that picture as our freebie. So your free picture doesn't need to be the one taken at the Meet-n-Greet. (Some say it doesn't have to be with a character, but that seems to be left up to the person helping you at the photopass place.)