Too Much Vector?

One of the more frusterating parts of the design process was realizing that Vector images, as
small as they can be, are extremely memory consuming when they are redrawn on the screen. Why
is that? Basically, vector images aren't really pictures, so much as instructions to a PC on how
to draw a picture. The PC is then force to redraw the same image from the instructions over and
over while the game is being played. You can see even with a few people on the screen it slows
down dramatically. Even in low quality mode there isn't much Flash can do for speed.