What the hell are you talking about? bad company 2 is flooded with hackers. try to google "Battlefield Bad Company 2 Hacks"
and then shut up
Wrong!
Wallhacking is when you can see people trough walls
the problem is that modern fps hacks is just a dll you inject in to the process that hide itself before the antihack program loads, therefore its impossible to stop fps "hacking" with the technology currently available
X-Trap, Gameguard, Punkbuster, VAC, etc. they all fails, they might stop the simple speed hack and stuff like that but besides that they are useless.
and it does not matter whether or not the game is free or not, look at how many people who are botting in WOW......

