We got a donation. I contacted the donor. They said no to getting a sticker. I think I should capture that so we see the difference between declined rewards versus no answer yet.
@Salt what should we do?
I think you should track it simply for inventory accountability reasons. If you have n+ amount of donations but still have n- amount of rewards in inventory, that isn’t going to match up.
Furthermore, when you start to run out of rewards and need to purchase some more it will give you a greater idea of how many you need to buy based on your previous pattern.
Not that previous market conditions are an indicator of future conditions. 
1 Appreciation
Yes, and getting CiviCRM back fully working and designed to handle this sort of data adequately will make looking at this all more feasible.