That was it for me to. The nostalgia of Transformers, the fights, the FX and I also don't think the story was that bad. I could probably come up with a list of 10 actions movies I have seen over the last decade that were worse in that department. Half of them might be Bay films.
Also, there is nothing wrong with enjoying some shallow entertainment once in a while. It's the equivalent of people eating fast food once in a while versus a really good meal. It's a guilty pleasure.
P.S. Our mindless entertainment is not just an American Culture thing either. Many of our "mindless" movies go over the pond and do blockbuster business over there as well.