this is not meant to excuse their lack of consideration, but i think a large number of men are completely oblivious to their body odor. i am constantly amazed how many times i encounter high level professionals who seem to have no idea how strong their stench is. i know some people that think by wearing obscene quantities of cologne that their underarm stink is masked, when the rest of us know that it isn't. this applies to breath too, i can't tell you how many times i've had meetings with people whose breath smells like a skunk crawled down their throat and died.
now for people who are concerned about metals like aluminum being used to control perspiration, there are "natural" alternatives to the chemicals that the big companies use, so there's no excuse to smell like rotting pepperoni, people!!!