You bring up a good point .
On a lease you only pay tax on the payment. On a purchase you pay it on the net price after trade. So if you are buying a 50k car and live in a state with 8% tax why would you want to give $4000 to your state to hold when you could be investing it .?
That is also why states like Texas ( iirc) dont allow leases . They want their money now ! You can however do a "smart purchase " which is a lease that is not called a lease but you pay tax upfront.
