Well, also keep in mind that, if you have the original install disks, you always have the choice of reloading loops you've gotten rid of, albeit a potentially tedious task.
Using loops is an art in itself if you don't want to sound like everyone else in the world who has ever used that loop... but programs like GB, Logic, and many others, allow you to manipulate them in so many ways that it's really just a question of how much time you are willing to put in on the project.
There are people on this site who use loops in ways which totally transcends the original loops themselves.
I love it that we can make our own loops from scratch (singing, playing an instrument, sound effects, etc.). Then one gets the benefit of having a library of loops to play with while never using anything which didn't come from your own abilities/thought processes/skillsets.
I have two loop libraries - one is the loops which I've gotten from Apple and/or free loops from here or elsewhere, and the other is made up of nothing but loops I've made myself. That way, if I'm trying to make a song which is totally original, I can use the latter library and not have to worry about it one way or the other during the creative process.
Last but not least, it's fun to compose using Apple and free loops to shorten the time it takes to get a certain effect or feeling. Then, go back and redo it all yourself, playing something which it inspires in you - some people could imitate the exact output but, for me, it's more fun to get inspired and then do something not entirely the same.