You are saying that buying maybe 10 games in a month at an average price of $5 per game is a rip off, just because you may win?
Why not buy the game when it is cheap and change your wishlist? There are a good 20-30 games I want, I can't afford to buy them all even at the prices on sale and that is even if they come up, so buying some of them, and so far spending ~£30 and getting 8 games, and maybe getting others, some of which I can guarantee won't come on sale, is hardly a ripoff.
If you buy a game then win it, give it away, it is nearly Yule after all, do something good for someone rather than being sore because you got a good discount...