Sometimes the real market failure is just that a market exists at all.

Like, in some really fucked up neoliberal hellscape it might make sense to charge money for reservations separately, but that introduces all sorts of extra new inefficiencies that weren't there before. Like, now that reservations can be bought and sold, it's now legal, possibly moral, and most notably, profitable to hoard them. And since reservations are a derivative on the underlying capacity of a restaurant, you're going to have tables that are "reserved" but unused because the "owner" of that reservation happened to sell it on to a third-party vendor that's now trying to hike the price to last-minute diners.

Meanwhile, the actual restaurant trying to sell food, can't sell food in their own restaurant, because their salesfloor is full of empty tables that are worth more to the market dead than alive. They are undergoing demand destruction as they are involuntarily transformed from a food vendor into a landlord of tiny plots of real estate whose desirability has long since been detached from any surrounding circumstances.

The argument for markets is that unregulated commerce is very good at calculation. Or, more specifically, that price discovery is the process of putting bounties on better information than is currently available. The flipside of this is that everything around the market needs to be regulated or you're calculating garbage into garbage.