A: Because adding a buddy is being nice and putting someone on your ignore list is being mean?
Just guessing. The obvious reason is of course “that’s the way the software was written.”
Not that niceness is our primary raison d’être here at the Straight Dope anyway, but I for one am happy that it’s harder to put people on the ignore list since IMHO putting people on the ignore list is Not A Good Thing (but that’s already been debated in ATMB.)
There is no limit on the number of people you can put in your buddy list, and I imagine it’s the same for the ignore list but I will verify that.
Concerning buddy/ignore lists - please read our guidelines in the “posting guidelines” ATMB FAQ sticky thread.