Everyone loves good swag, but the key to motivating the behaviours you want to see in your community is focusing on intrinsic rather than extrinsic rewards. Intrinsic motivation is based on internal incentive such as pleasure or interest, so the key to rewarding appropriately is to support those behaviours.
This is a companion discussion topic for the original entry at https://blog.discourse.org/2022/11/enough-with-the-water-bottles-and-t-shirts/