they might not be able to see the purchases if you're in a state where you can buy booze in a 7/11 or grocery store; in that case it's just a grocery purchase. but they sure as hell can see that you have a charge from "CORNER LIQUOR STORE - $47.61 - 12 APRIL 2024" and can make guesses.

This also assumes that grocery stores aren't aggressively aggregating and selling sales data, esp. those from Membership Cards. Insurance companies would love to get a hold of that data, not only for alcohol, but things like sugar and junk food purchases. I'd bet my hat they're already doing so.