In theory, it could re-invest those profits into the company, in hopes of further gains down the road. (But like all things, there's a healthy balance.) In practice, I think the answer is "executive bonuses" and [short-term] "stock buybacks".

(But morally I agree; there is no reason every company has to be Scrooge, and I think it's to their long-term unprofitability to be so, by effectively ensuring a lack of experience & growth within the employees generating the value in the first place.)