From a customer perspective, this practice feels very disingenuous. The 5.95 should be labeled as part of a delivery fee.
If somehow DoorDash was the first link a user visited after searching for "donut plant", they would need information to decide whether to visit the restaurant or to order online.
The transparent thing to do is to list the 5.95 markup as DoorDash-imposed. That way the user can easily see their choice