Why?

It is economically inefficient. Scalpers create no value and destroy some by spending their time.

Scalpers transfer goods from those with lower willingness to pay to those with higher willingness to pay. This is by definition increasing economic efficiency. Rationing of scarce resources and all that.

Transferring goods from those "with lower willingness to pay to those with higher willingness to pay" does not increase economic efficiency, it changes the allocative efficiency. But at scale, in many situations, scalping merely becomes rent seeking. Rent seeking reduces allocative efficiency. How much the rent-seeking of scalpers offsets the allocative efficiency is up for debate.

But all of this is sideways to when and whether scalping is moral or, at least, preferable in society. Not all actions which increase allocative efficiency are things we actually want in society.

Otherwise, kidnapping and ransoming children back to their parents would be a boon industry.

The first paragraph is only true if you believe the supply is fixed (ie the elasticity on the extensive margin is zero). This is often a good way to teach economics because much of the math remains the same in a production environment but when you apply it in an environment it isn’t designed for it leads to fallacies like this one. Free markets and capitalism work precisely because it isn’t a zero sum game like this.

And your last two paragraphs are nonsensical, you are comparing the right to eat at a top end restaurant with the right to not have your kids kidnapped it’s downright laughable that you’d see such a moral equivalence.

It’s hard to take a reply serious from a person who doesn’t understand analogies.

I understand analogies just fine, your analogy is just ridiculous because you analogize kidnapping and ticket scalping.

The rationing already occurs in the reservation process, without money changing hands.

> This is by definition increasing economic efficiency

Bespoke markets are by definition economically inefficient. There's a reason most people buy mass-manufactured cars, and it's not just the cost, it's that bespoke car production cannot make enough cars to meet demand.

At absolute best a bespoke market may sell a few more of a limited set of dining opportunities to others through the additional marketing medium. At better what bespoke markets do is maximize profit taking. At bad this maximization of profit taking channels money to the middleman that otherwise would have gone to the merchant (as there will be people who pay for a reservation and then order the cheapest meal at the restaurant, as they can't afford more). And at worst this makes it inconvenient for people to frequent the restaurant, resulting in an overall reduction of customers. The bad and worst circumstances can result in fewer operating restaurants. And artificial resource scarcity is the opposite of economically efficient.

If scalpers (who have overheads of their own) are making money then that implies the restaurant is doing the economic equivalent of leaving a lot of $100 bills on the floor. Before those bills were being picked up by random customers but now they are being picked up by people who heard there were restaurants leaving $100 bills on the floor. But the cause is ultimately the restaurant choosing to just give up free money by not charging a price so that supply and demand equal and the market clears.

You're assuming my "bad" and "worst" scenarios do not exist. And also assuming that knock-on effects don't occur which cause issues in other parts of the economy. A cartoon-like example: spend X+Y money to dine at restaurant, spend -Y less money elsewhere, people working elsewhere are laid off and can no longer afford to spend money at restaurant. Restaurant loses customers. Restaurant closes.

If that happened then the scalpers would go out of business first as demand at the face value would be falling closer to the supply.

Mutually assured destruction does happen. The problem is if there are more potential scalpers who are convinced they know why the previous scalper failed than there are restaurants that can absorb the hit.

Yes, but the restaurant has set prices they think are appropriate for their food. They want to be open to any customer willing to pay $x per person to eat, more or less. Scalpers make it so that people who can only barely pay $x per person are supplanted by people willing to pay much more. These people have higher ability to pay, but that doesn't mean they will receive as much utility as the people who are being priced out.

The restaurant cares about increasing people's utility, not about only serving a the wealthiest fraction of people who can afford their food (those with the highest ability to pay).

The restaurant is free to require names upon making the reservation and checking IDs.

The market already does that.