The problem is there, those who dare to take risks by accepting payments using bitcoin or other cryptocurrency are those who have large-scale businesses / organizations. Very large and fast fluctuations in value can be very detrimental and risky so this calculation and revenue management cannot cover the worst losses when accepting bitcoin payments. The absence of a third gate that facilitates this also becomes an obstacle because they cannot take too much risk and choose a local currency or FIAT to further reduce risk in doing business.
Based on this, paying with Bitcoin would be like paying with Gold. A volatile cryptocurrency can never be used for mainstream commerce because it reduces the chances of profit. Merchants and businesses are better off using centralized stablecoins than Bitcoin because of its highly-fluctuating prices on the market. But who knows? If Bitcoin becomes extremely popular and widely adopted in the future, supermarkets and retail stores might be able to accept it as payment method. We already have centralized payment gateways which allows merchants to accept crypto transactions with ease. As the regulatory landscape for the crypto industry matures, we might be able to buy actual food or groceries using Bitcoin directly without having to convert it to Fiat, ever. Everything will depend on customer's demand for Bitcoin as payment method for in-store purchases. If demand for Bitcoin is high, then merchants and businesses will begin accepting it as payment method. Otherwise, using Bitcoin directly for food or groceries will be more of a dream than anything else.
Nonetheless, time will tell us what lies ahead for the future of Bitcoin and crypto as an alternative payment system towards traditional Fiat. Governments will play a key role in determining this future as they devise laws that would either stifle or stimulate the growth of the entire crypto industry. A regulatory-friendly landscape, alongside price stability on the market, will make Bitcoin and other cryptocurrencies more attractive to businesses and institutional investors. Just my thoughts
