I don't believe I said that they lose money, you're making an assumption there. Negotiation doesn't necessarily mean someone gets the short end of the stick, unless you go into the negotiation not knowing what to expect and unprepared.
Let's use your example. Lets say that you're paying $350 for your lease and I'm paying $650 for my purchase at 2.4% (market rate). Let's also say that we both bought our cars (same model, same price) at the same moment in time from the same place. We both decide to trade the car at another dealership at the same time, the first day after month 24. Who comes out ahead, and why.
Omg I've explained it several times. I'll try again.
2 cars- Selling (not MSRP) Price of $30k.
We'll use a 60 month loan vs a 36 month lease for simple comparison. We'll assume both are paying taxes upfront.
Loan- takes bank loan for 60 months. 2.4 apr.
pays $2100 in taxes (7%).
Let's say payment is $600 per month to keep it simple.
Lease - Pays the amount between $30k and the residual value determined by the manufacturer. (Let's use $20k for residual).
Money factor at .002
Taxes due- $700
Payment $300 per month.
Over 2 years the "loan" person paid $16,500
The "lease" person paid $7,900.
Both have no negative equity. Same result. One paid $8,600 more over the course of 2 years.
Oh wait, let's add GAP insurance.
Loan person- paid $800
Lease person - paid $0
Now the difference is $9400.
It's math. There's nothing that could ever make the "loan" person come out ahead of the "lease" person in this scenario.