Why don't make the refund tokens three every season?

The refund system in league is pretty useful but if we used it all we'll never get to refund anything ever again. Riot said that you cannot get more tokens and 3 is just there and you cannot get anymore. I wish they could make it like 3 more tokens for every season because if you acidentally purchased something or your friend decides to come on your account and use all of it then you'll never get another refund.