I care for some things, but rarely. Quite often, if I want a certain set, it's because of a certain part or baseplate or klicky that I want to use for something else, usually for the zoo. So as long as the set has the parts I wanted it for, I'm good and don't care about the rest. On rare occassions, i want a set exactly as it comes, though, particularly certain specials, etc.
Anyway, so to answer the original question, if they charge a lot, yeah I hate that. But I love finding an incomplete set that has the particular things i'm looking for out of the set, marked way down because it's missing some other stuff!