Actually, no, I'm not wasting money. I've done the math.
1) For cash, superRich has basically the same exchange rate as wise.
2) My credit card has no fees, gives a good exchange rate plus 2-3% cash back on every purchase. That easily beats wise, so I put everything I can on my credit card.
3) My ATM card has no fees, a good exchange rate, and even refunds the Thai ATM fee. I think wise still gives a little better exchange rate, but not by much.