Giving SSN. Bad idea or doesn't really matter?

Long story short. I play 2 days a week. I've never cashed over 10k, but they "require" my SSN sometimes when I cash out (usually anywhere between 3k to 9k when I cash out and they ask). I've always refused. They denied cashing me out last week because of it. Last night they tried to again. I got lottery to come down. They cashed me out but the cashier said for now on they will refuse if she sees me.

I just really prefer not to because it's my SSN. I've had someone who somehow got a hold of it open jewelry store accounts in the past then pawn a ton of jewelry under my name. I have nothing to hide. No kids so no child support, I don't owe the government money or anything.

I've been told by other players never give them my SSN. I've been told by others it's not a big deal at all. Just curious as to what other people think.