This reminds me of grocery shopping. There is an express lane for people with 12 or FEWER items. I've NEVER seen a cashier working that lane turn away a customer with way more than 12 items. I'm sure they've been told that the customer is always right, and I imagine that unless it's a legal thing (underage drinking) or a safety thing, that a lot of CMs just don't feel comfortable telling a guest to move along.