Man, just how often are you at walmart? I shop there all the time, way more than the average person and I've never once had the alarm go off. But if it did, you can bet your a$$ that I'd stop and let them check my stuff out.
When the alarms goes off on people, it's normally because a cashier who's not paying attention, didn't disarm one of the little tags in something you bought. It's not the fault of the door person so why give them or the whole store a hassle about it? Go back to the cashier and tell them "PAY ATTENTION!"
It just feels like an invasion of my privacy.
Also if everyone just rolls over what prevents the store's (Not just Wal-Marts) authorities from outright profiling certain groups?