"...at a minimum, they will substitute a 30% fee with a 4% credit card processing expense..."
Which large corporation is paying anything close to 4% for credit card processing? Based on what's available to me in my small business, I'd be astonished if anyone doing any significant volume was paying as much as half of this percentage.
Are you selling something with some utility to adults? And as a consequence you have zero to very few chargebacks, because your customers aren't going to be overriden by their parents?
I can imagine there are a lot more problems with kids' spending on Roblox, which would bring the processing fees way up.
Which large corporation is paying anything close to 4% for credit card processing? Based on what's available to me in my small business, I'd be astonished if anyone doing any significant volume was paying as much as half of this percentage.