Given the situation - the potential of receiving *years* of themed gifts that you don't want and won't use, I think having your husband drop a tactful word to his mother and sister, and at the same time have a few suggestions for things that would be good, and not too hard to get.
I don't collect anything collectible, if that makes sense - I've got tons of books, a reasonable number of DVDs, and lots of CDs, but no themed knickknacks or charm bracelets, and I actively don't want to collect stuff, because I'm just going to have to throw it out the next time I move, or if we have a kid and need more space.
What I've told relatives who want to know what to get me is that food and drinks is good, and so is music. The former is consumable, so I enjoy it, and don't have to store it, the latter is compact and I have wide ranging tastes in music - the chances of duplicating something I've got are slim, and I like checking out new stuff. Plus, with both, if I don't care for it much, it's easy to hide the fact.