We've had a given name (or a close variation of it) run in the family for some generations (6 that I can immediately think of) but usually only for the eldest son in the generation. However, because most have not been called commonly by that name it would somewhat difficult, although probably not impossible, to use each others FF miles and/or tickets. While I think is sort of a nice practice, my teenage son is not so sure (of course, he didn't have a choice).