You couldn't be more wrong. It's quite common that leasing a car is cheaper than buying it new and then selling it after 3 years. Just that alone makes financial sense.
That is true, but the argument most people who wont lease a vehicle make is that "why would I ever get rid of a car in 3 years?!?!?!?!??!?!??!?!?!?!!?!?!?!?!?!" (exaggeration intentional). Buying a vehicle usually works out better than leasing, somewhere around the 5-6 year mark. After about 6 years, the person buying the vehicle is usually ahead of the person who is leasing, who would have 2 cars during that time frame and still be making a payment.
Before 5-6 years though, if the comparison is "buy new and sell after 3 years" or "lease and trade in and re lease after 3 years", its normally fairly close, with some special circumstances / incentives possibly making leasing cheaper.
(not directed at person I am quoting above)
What normally amuses me, is when people take a hard line stance on something like this, like they know whats best for everyone. As was said earlier, Its pretty silly to have a discussion about "financial benefits" in a forum about buying cars that cost 80k+. There is no world where purchasing an 80K tesla provides any financial benefit, no matter HOW one pays for it... all cash, lease, loan, whatever.
There are plenty of other vehicles one can purchase to go from a to b that dont cost this much, and would fill the need of transportation. So, now that we have acknowledged that there is no world whatsoever where a model S purchase is a "financial benefit" in any way, shape or form, we have established that its a WANT, not a need. How people pay for "wants" and what they want is a personal thing.
I like nice cars, so have been driving BMWs and recently my model 3 performance. My sister drives an econobox minivan because she really doesnt care about cars, but has a collection of luis viutton purses. She thinks my cars are extravagant, and I think its silly to spend 1k+ on a purse. We all have things we will spend money on, that makes it worth it to us. Cars, cigars, golf, vacations. Most of that is not "financial benefit", but makes the person happy.
This debate has been around so long, that I am virtually sure that this post was made just to "get discussion going" as its a topic that can guarantee strong action on both sides of the discussion. There is virtually zero chance this OP didnt know that, but we all fell for it anyway.