Waiting 30 seconds to pay for a coffee may seem like a small inconvenience, but it's still much better than waiting for a transaction to fail because of a NFT drop. The process of paying for a coffee can be quite lengthy, depending on the store and their payment processing system. You may have to wait in line for a few minutes and then go through the prompts at the POS terminal. After that, you may have to wait for the credit card verification to process, which can take up to 30 seconds or more if the store's POS terminal is on a slow connection. Finally, the charge may be pending for a few business days before it comes out and the vendor has to wait 3-5 business days to get the funds from the sale, although in some cases it may be as little as 1 business day. All in all, it's quite a long process and having a system where the whole transaction is settled in 30 seconds or less sounds like a great idea.