Yes, its their choice. And when the business fails, its also their fault.

There should be different pricing for what currencies force you to do. If you never deal with XMR, like myself, then accepting it would probably increase the cost of my services to account for me having to go through a hoop to end in Bitcoin. If they want to do that instead and reap the benefits of paying me in my unit of account, then great. I wouldn't say no to any currency that I can reasonably trust it's ability to be changed into bitcoins. If the reason for not accepting Monero is that you don't want to waste your time with all that, or find it difficult to flip into your unit of account then that's understandable. Yet, I'd be remiss if you didn't charge more to make it worth your time - that's kinda lazy & dismissing the fact that people want to spend money they have with less friction. Merchants should be willing to deal with more friction than consumers.

You seem to know from experience.

Fiat ruins whole countries. A cancer upon society.