Yet another shiny example of money vs. ethics in the Valley.
Also, don't look towards the engineers, who may or may not have known. Look towards the money. Who are the VCs invested in them and how many of them knew and encouraged that in the name of growth? And, of course, the executives.
Not really. Elsewhere in this thread, people pointed out that there's a clause in the contract that allows this. So whoever was higher up probably told them (rightly), that it was a service that restaurant owners wanted. I mean, who doesn't a free website generated for their business? They'd need to dig deep to find how it was harming the business.
Software developers are not that dumb. The most likely scenario is whoever coded this knew what was going on (maybe not all the details) but chose to ignore, because paycheck. Same with other shady stuff like dark patterns, facial recognition (like Amazon's) and so on...
Also there is legality and then there is ethics. Something in the contract might be perfectly legal, and yet unethical.