Bitcoin is at $10,000 and shops/stores gets $50,000 payments in Bitcoin and after that if Bitcoin price falls to $5,000.
Shops/stores will lose $25,000. Will people take Bitcoin payments for goods and services
?
As said by others, most shops don't get Bitcoin. The payment processors do. And in my experience they change the price in Bitcoin really depending on market price, to keep the price in fiat unchanged.
The payment processor has a quite big margin of profit, margin that means more profit when Bitcoin is rising and a small profit or even a loss if Bitcoin is falling.
It all depends on the size of the margin, how fast the price of Bitcoin is changing at the moment of your purchase and the payment processor's policy on selling (if they sell, how fast do they sell) of the Bitcoin.
If they are smart (and I guess they are) they have funds on certain exchanges and as soon as you do the purchase, they trigger the sale on the market. The value of the deposits on the exchanges may decrease, but that's not lost, that's an investment and their business will continue to go on.
Imho there's slim chance the really big payment processors will go out of business because of Bitcoin fall. They earned a lot when it was growing so they can easily cover the very few transactions they may have done at a loss.