The unethical part is Doordash's predatory pricing. There's an aphorism "You can't cheat an honest man". Probably not strictly true, but it applies in this cas

The unethical part is Doordash's predatory pricing. There's an aphorism "You can't cheat an honest man". Probably not strictly true, but it applies in this case. Anyone who takes advantage of this is doing the world a favor by punishing bad actors.