Ok - I'd like to add a slightly different scenario here. I was on a flight where all I had with me was a laptop bag. It also contained a couple of books and maybe a newspaper. I purposely checked my 22" roller so that I could store my laptop bag in the overhead bin so I would have my leg room free. I get on and put my bag overhead and the FA comes by and says that all small bags need to go under the seat. He takes it down and tells me to put it under my seat. I protested but gave up after he told me it was "a rule" blah blah blah...need to fit all the big bags overhead, etc...

Just made me annoyed that if I wanted a bag under my feet I could have also brought my larger bag on board and suck it overhead. I should be penalized because I chose to check my larger bag whereas others didn't.