The most important benefit of accepting Bitcoin i could think of at the moment is the fact it's like an payment with possibility of more profits. Let's say if I have received $10000 as a payment and in a week the akue f Bitcoin increases by 10% then I would have $1100 if I hodl it.
But I strongly object to your point saying it's cheaper than western union, I think you should check the transaction fee during bull run or when Bitcoin's value is higher.
It's not an advantage for a business owner who needs to pay bills and operates on small margin. You may not know this, but most resellers get less than 5% in profit.
This is especially visible in the cost of gasoline, but also new cars, apartments, and many other goods and services.
Let's say you have a car dealership and the cars sell for $50k and you get 5%, so 2,5k in profit for every car you sell, but you have to pay staff, electricity bills. When you subtract all of that you end up with maybe 1k in your pocket. By the time you're done bitcoin goes down 10% and you have $250 less. It can go up, but you can't wait, you have bills to pay, so you sell at a loss.