I always say I don't collect anything because my mom has TONS of "collections" and I'm an only child, so one day all of those....will be mine. Salt & pepper shakers (which I think are no longer an 'active' collection & are packed up in the attic?), pretty dishes, teapots, snowmen... yikes. When my cousins say "I love this snowman platter!" I tell them, "you can have it someday, but it will come as a set with all the other snowmen!"
I use to collect moose figurines. Actually, I didn't collect them, I just got a bunch as gifts all the time & didn't get rid of them. My favorite animal is a moose--even though I've never seen one IRL...but that will change as we're moving to ALASKA in July!!!!!-- and the problem when anyone knows you have a favorite anything is that you end up with a bunch of them. My moose items are all packed in boxes somewhere. They're cute, but I would need a "Northwoods lodge" themed home to display them, haha.
I do collect Christmas ornaments: we get the Hallmark decade series every year plus one on vacations (or keychains when ornaments are un-findable). I often pick up a familiar book in a foreign language when traveling too.
DH collects money from different places we live & visit. He also 'inherited' a bag of coins his dad collected.
Of course I have lots of fabric, yarn & craft supplies, but I don't consider those collections. They're just things that are waiting to serve their purpose