Total wine checked my id and wrote down me and my girlfriends name

For context, me (22) and my gf (21) went into total wine today. Baileys was there with a tasting so we provided our ids, which they wrote our names down and went about trying their new chocolate flavor.

When we got to the counter to checkout, the cashier looked at our ids, and asked for the manager to come over. He gave my gf’s drivers license to the manager and then wrote her name down on paper before we did the transaction and left with our alcohol.

I got to wondering, why did they take our names down? Was it for a background check or something? I don’t really understand.