I've purchased some services and bots for online games via discord servers. There are different methods of servicing payments, but the most common and convenient that I've used was Coinbase Commerce. Essentially, the vendor sends you a link to Coinbase's site, and on the page you'll be given an address and amount to send. Once received, the vendor gets notified, and they utilize various other discord bots to facilitate the rest of the transaction.

It's quite sophisticated, yet it's streamlined and very easy to use. When I first tried Coinbase Commerce, it was a eureka moment for me as crypto was legitimately providing a niche service whereas there was no viable alternative. Vendor's could accept in-game currency, but they risk getting their accounts banned; some vendors are from very poor countries and cannot accept USD or other foreign currencies; transactions need to be quick and verifiable as there is a high level of trust involved.