I don't like labels on anything I own, so I don't add them to my quilts either. I don't usually like how they look on quilts, actually, I think they're often too distracting. I rip labels off of everything I buy, so it seems counter-intuitive to sew labels onto something I've made. Neither of my grandmothers labeled their quilts, so to me, a "traditional" quilt doesn't include any labels anyway.
I've bought labels a couple of times, because I've been told I "need" to label my quilts. But I never use them, so I've given up on the idea. Labels are for others, I guess. I don't feel the need or desire to use them myself.
I actually really hope none of my quilts last long enough for someone to wonder who made them - I hope they're used so much they fall apart long before then!