If I have lots of edge points, I can afford to spend some, knowing I will not miss out on the expensive edge as a result of having too few edge points left. I might miss out for some other reason but it won't have stopped me taking edges on the way.

As it is, I can't take edges on the way because I need every edge point I can get, potentially, to have a shot at that edge when I hit old age. At which point I might find that I can't get it anyway. So no good edge and hundreds of edgeless hours to find that out. With more edge points I wouldn't have the hundreds of edgeless hours.

Also edge prereq doesn't tell you about imm exp requirements if I remember correctly. And if you are going for champion of man edge, say, I think that may have such a requirement. And the rp required for it probably shuts off the easiest route to imm exp, which is worshipping an imm.