Dealer gets car from proton for RM20k
Sells the car for RM60k
for BTC payments, charge 1 BTC for it @ RM65k

That's RM5k profit. But actual profit is 65-20 = RM45k @ 1 BTC

BUT

Actual transaction for the dealer is they get 1 BTC for RM20k. Sell BTC for RM60k, makes 40k per car.

For those who've been holding BTC since USD1k per coin, you can get a car, with no bank intervention, for RM4k.

Win-win for (almost) everybody.