So what does commission-free actually cost a restaurant?
Three costs, and none of them is a share of your food. First, a flat monthly software fee for the ordering system, billed the same in February as in December. Second, card processing, which the payment network charges on any card transaction anywhere. Third, delivery, but only on the orders that need a driver, and only if you offer it.
The useful question is not whether a system is free. It is whether the cost is fixed or variable. A flat fee is a line item you can plan around: it does not move when a food blogger posts your shawarma and your Friday doubles. A commission is a permanent tax on growth, and it is charged hardest exactly when you are busiest.
Divide the flat fee by your direct orders to compare them honestly. At 500 direct orders a month, a $499 plan is about $1.00 an order. At 1,000 orders it is about $0.50. A 30% commission on a $40 ticket is $12.00 and it never gets cheaper.