That is what it says after all, it's pretty explicit.

It's just such a bizarre choice that one might hope there would be another interpretation. Why measure a percentage change on sales tax, which varies heavily from location to location, and is not what the associated fees are based on, rather than simple choice of total cost?

	▲	post-it 8 hours ago \| parent [-]
		Because sales tax is something you pay that's more than the sticker price, and people tend to have an intuition for sales tax in their area. Personally, I find "a 3% credit card fee is like paying 21% more in sales tax" to be intuitive.