The US has a highly regressive tax system, at least for middle class earners and up. We do everything that way.

No it doesn't. The fact that a 7k deduction doesn't help middle class people proves we don't have a regressive system.

The US middle class is relatively lightly taxed.

I think this helps the middle / poor class. Rich people lease expensive EV that would normally not sell. After 3 years rich person gets a new car and EV sells for peanuts. Just look at the cost of a used Nissan Leaf right now

It's a set amount money set aside to jump-start the market. The subsidies will end when the fund runs out and pure (if there is such a thing) market forces take over. Fossil fuels are subsidized permanently, however.

"pure market forces" won't take over until the negative externality of pollution is properly priced.

Market forces alone will never fully price in pollution, IMO. There's no incentive to do so without regulation, and even if there were, I don't see how price discovery would work. The environment is not a market participant, unfortunately.

Anyway, this is pretty far off the original question of why EVs are being subsidized via tax rebates in the US.

And they get reserved parking spots at many deprtment store stoo, at least in CA.

In my area when the first wave of EV spots went in they tended to be very 'premium' spaces. I think this was a result of novelty. Recently they have been making them the 'worst' spots or at least not 'premium' spaces and I think this is a better move. It also has reduced the instances of people parking ICE cars in EV spots.

Early adopters help bring the costs down for everyone else.

By making the car more affordable for wealthy (but not that wealthy) people, it eventually brings the cost down for everybody.

Anyone that wants an EV ultimately benefits from the credits. Take a look at the prices of used EV's (other than a Tesla).