There is something called sweepstakes. Where when I buy a certain drink it gives me a “ticket entry” which if they pick it I can win something. I don’t care about it, I just want to buy the drink because every time I buy I get points which I can eventually redeem to get like a free snack. Is this ok

If you don't care about any of these things and you just want the product itself, then this is fine. If you are not buying specifically for these rewards that you mentioned (where you either win or you don't win, because that becomes gambling), then it's acceptable. If you just want to buy the juice itself, for example, then this is allowed, inshaAllah.