Agreed - BIS make enough from selling the military versions of the Arma series - VBS2 ( Arma is based on these). This is why Arma is so realistic and miles ahead of other games - the people behind it know what they are doing.
I also LOVE their DLC system. Everyone gets it. and if you're willing to pay £7 or whatever. You get the full rez textures. The SP map/campaign too.
But you are not forced to get it and if you're unable to afford it you dont get alienated from your friends.