I agree that ongoing infrastructure costs money, but several years of that should be included in the original estimate and pricing for the sale of the product. Plan for the sale price being cost to make+5 years of estimated maintenance for base product+profit margin. Then extend maintenance with each DLC if any. If no dlc then offer subscription to pay for servers and other infrastructure, if subscriptions fail to cover that then sunset the product but open source the server infrastructure so the community can pay to run it if desired.
I agree that ongoing infrastructure costs money, but several years of that should be included in the original estimate and pricing for the sale of the product. Plan for the sale price being cost to make+5 years of estimated maintenance for base product+profit margin. Then extend maintenance with each DLC if any. If no dlc then offer subscription to pay for servers and other infrastructure, if subscriptions fail to cover that then sunset the product but open source the server infrastructure so the community can pay to run it if desired.