Well, my bike didn't actually come with a stand (good old racing mountain bikes
), so I've lived with lying it on the ground for a few years (you can't flip it upside down 'cause it has hydro disc brakes).
Melissa, I think you'll find that the weight of the stand (~500 grams?) will hardly make any difference to the amount of effort it takes to ride (given the bike weights something like 16kgs). The only place where a light bike helps is going up a hill (I'm talking about a few kgs, not 0.5), and when accelerating (again, needs to be a few kgs - also taking weight off the wheels helps here too).