In my experience what drives great entrepreneurs is not a desire for wealth, power, or fame; it's a burning desire to make a small change in the world, usually in the form of bringing their product to market.
This is silly. Entrepreneurs are no more (and not necessarily any less) virtuous than anyone else who works. People have the whole gamut of motivations. In general, humans need something to do-- to keep fed, and to keep their spirits high.
There are plenty of entrepreneurs (even many quite good ones, in terms of effectiveness and moral character) who have the same pedestrian motivations as average people going to work: wealth, security, esteem, et al. Don't put them on a pedestal.