I know this is thread drift but I wanted to offer a different perspective on this.
It really doesn't matter if it's state law or not, I'm not saying it's OK for the employee to lie she may have honestly been told that by whoever trained her.
My point is that she was very likely told this company policy and failure to follow it could result in termination.
Where I work company policy dictates 100% ID check. I "check" IDs on people I literally see every single day. I check IDs on people who are literally going to take 2 steps past my desk and scan in through a card reader. I checked the ID of an Ice Vendor today who used to work for the same company I work for now I trained him.
My point is that it's company policy and I don't have an option. If I get caught not checking IDs I lose my job and in this economy and at my age I'm not ready to go out there and try to find another one. I get people that complain about the policy every day I tell them all the same thing "I'm sorry, I have no choice in the matter, if I get caught not doing this I lose my job.
So the next time you run into someone who tells you the have to do something stupid because it's company policy you can feel free to take your business elsewhere but please don't take it out on the person who probably agrees with you that it's a stupid policy but can't afford to lose the job