Years ago, Intuit merchant service refunded fee when you refund a customer. It reversed the 3% fee except a nominal like $0.25 per transaction fee. So you lost less than $1. It makes sense because they have no risk, which technically no money transaction after the refund. Commercial banks merchant accounts fee structure are still like this.

Recently we had a government customer used the wrong card initially for a close to $10,000 bill, and asked us to refund the 1st card and charged the 2nd card. We were being charged closed to 4.5% each time. In total Intuit charged us closed to $1400. What a RIP-OFF!!!

3%-4.5% transaction fee is to cover merchant account risk. There is no reason behind to charge another 3-4.5% fee instead of refund. It's like you return your purchase to the store, instead of refund they charge you again. UNREAL!!!