I have seen this at several European airports. However, if I think there is any chance I will be required to check my carry on luggage, I either rent a locker or keep the heavy stuff in my car until after I have gotten my boarding pass. I have never been challenged at the gate if I got one of those tags approving my carry on luggage.

I know this irritates alot of you posters here but I am only carrying on one small suitcase. Not the mounds of stuff other people get away with carrying on the airplane. I can't help it if I like to read and usually carry about 5Kg of books with me. It is certainly not my fault that many times the wait at baggage claim is longer than the flight.