I don't know if I would use it, but I think you definitely could use it.
When I was cleaning out my wallet a few months back, I found that my costco card wasn't actually mine at all, but some other woman's. I'm guessing they got mixed up at the cash register. I have no idea how long I used her card and vice versa.
That said, Costco will refund your membership if you're not satisfied. So you could get a membership, check it out, and cancel if you don't like it.