So you're a big retailer and you prefer not to use crypto despite the fact that it can double your profit margin.
On paper its a no brainer. So what is the barrier?
Accepting crypto isn't going to double anyone's profit margin, but it might well be an accounting and taxation nightmare. Not only legally but also in having to rewrite their in house apps and procedures. Big headache for a big company...
General retailers have an average profit margin of around 2-3%.
Credit cards firms charge 1-4% depending on volume.