You're super wrong. All of the purchasable legendary items have variants with different stats. I.E. Dead orbit is the only faction with legendary boots that allow you to carry more hand cannon ammo. Unless I get an legendary boot engram that gives increased hand cannon ammunition, I have no choice but to buy those. My friend for example haS the Crucible variant of the legendary hunter boots that do increase hand cannon ammo capacity. You can't buy those. Then there are the legendary weapons. FWC is the only faction with a purchasable legendary hand cannon, but my friend got a dead orbit hand cannon in the mail once reaching rank 4. There's also faction shaders, faction exotic class gear and even faction vehicles.You CAN'T BUY THOSE.