I don't want to derail the thread with all of the reasons I hate it but I will say that I personally think it sticks out like a sore thumb. My eye is immediately drawn to it during press conferences and cutaways to the dugout. It's particularly bad when the flag is white and the background is navy or black.
I get what you're saying about 'pop' but I feel that the batterman does a good enough job of spicing caps up. Another logo just clutters the cap AFAIC.