So this scenario isn't acceptable
Person A: Man, I want an EV, but I don't pay federal taxes anyway. Seems a waste to not get the credit
Person B: No worries, I'll buy it, claim the $7500 tax credit and then immediately resell it to you for $3750 less than my purchase price. That way we both save!
On the other hand, if you buy an EV (and likely register it) and then find that you hate it, then you can still sell it (had a coworker do this - she was a former fighter pilot and hated all the safety features taking so much control from her)