Do you see internet piracy as a sin? By that I mean downloading of movies,books,music etc.
Generally speaking, yes, since it violates the Seventh Commandment (Thou Shalt Not Steal), but there are possible justifications (such as an abandonware or shareware game that someone suddenly starts charging you for (company buy-out deals, usually)).
If you have the money, you ought to pay.
If you don’t have the money, you ought to wait until you do.
If you’re questioning buying a game because the company supports , then you should really be asking yourself whether you ought to be playing the game at all.