I understand what you are saying, but for goodness sakes, it's not the IRS. Surely, there should be some flexibility in the enforcement of every rule. After all, the customers are forking over some money for the privilege of flying on the carrier.

I agree with others who say the airline should take the bag and send it on through with the understanding that if it doesn't make your flight then the airline is under no obligation to deliver it as a lost bag at the destination city. The bags-must-go-on-the-same-flight-as-the-passenger rule was put in place before all of the bags started being screened by TSA. Lord knows that bags get involuntarily separated from customers often enough, and travel on different flights, that an occasional voluntary separation wouldn't be that risky or disruptive.