It's a color, I'm kind of shocked that you're bothered by it; unless, of course, you're one of the men who are so insecure with themselves that even the color pink makes you feel uneasy.
And since when do you watch football worried about whether or not a team's uniform colors mesh?
Awareness, yes everyone know's of breast cancer, but the pink on their jersey's bring it back to mind rather than an afterthought. Is it a scam for some companies to make money off of? Probably, but it also raises a crap load of cash for research that could help both breast cancer and other related diseases.
Why not all the other diseases out there getting games dedicated to them? Because you can't have a game for every darn thing out there, so it's nice to pick one and stick with it. There's charities and funds and parades and what not for all types of disease, quit complaining that they're not ALL represented in this one case.
Not really, its a great exercise for a lot of reasons. A lot of guys do it to show off, but its still a great upper body exercise. Its compound, so it works plenty of muscles. Pair it up with pull-ups and you've got pretty much everything worked.
Can it be substituted with other exercises? Of course, but so can anything else.
Edit: How it relates to playing football? Not a very strong correlation I'd say. I don't see why they don't do more explosive type of lifts (cleans?).