Oh dude, you don't get the problem. Currently my IDE eats up 10Megs and it currently compiles. File manager is eating up 14Mb. Age of Connan patcher 150Mb. Firefox with only 5 tabs 201Mb (ROFL wtf?). I'm planing open at least 1 more Photoshop and a 3DSMax instance.
Get this, you don't necessery need to allocate all availabale memory. It could be used by other applications.