I'd be curious to see how many companies that accept bitcoin actually get a significant portion of their purchases paid for in bitcoin. Because yes, if someone is willing to take the stuff that's roughly worth as much as used toilet paper (over time anyway), why would I offer them my bitcoin instead?

This is why at least a good few folks accepting bitcoin do so at a discount to fiat, just to make up for the savings they get by not needing to pay card processing fees or on ramp fees to buy into Bitcoin themselves. Popular discounts I've seen are 10% and 8.21% (a nod to infinity/21M).