This is pretty standard for flat pricing nowadays, but hits certain types of merchants really hard.

It's a double whammy when you have a cancellation and have to refund and then lose 3% on top of that. Stripe should keep the fixed fee, sure, but keeping interchange doesn't seem right.

Why doesn't Stripe offer the option to do simple interchange+ pricing to all instead of restricting that option to 6 figure volume accounts with negotiated agreements?

That would cleanly solve the issue and be fair on both sides.