I can tell you that there are places (Global) where they accept bitcoin via Binance, e.g.. that is, you could pay with any crypto, it's obvious.
Nowadays you can pay with bitcoin anywhere in the world, literally, obviously you have to get the right place, not everyone puts out the ads.
On the other hand, it does not make you a better bitcoin user to pay strictly with bitcoin, the fact of trading with bitcoin helps, so in some countries arbitration allows significant gains.
In fact, that same situation is what has made many commercial establishments accept bitcoin, they earn with the subsequent trade of bitcoin to Fiat or cryptos such as USDT, sometimes it is not that they are adopting bitcoin for their premises or it is the alternative means of payment, No, they just see profit.
fM (̿▀̿ ̿Ĺ̯̿̿▀̿ ̿) ̄
The adoption of BTC for payments is a very delicate subject. After all, merchants and/or businesses don't want to be flagged as tax evaders by the government. Those that let their customers know they accept BTC, it's probably because they accept Fiat on the side. A Bitcoin-only business will bring unwanted attention by the government itself. At least, Bitcoin holders are not left "empty-handed".
I don't mind if the merchant converts BTC to Fiat, as long as he accepts it as payment method. One way or another, this benefits the crypto economy. I'd say most businesses accepting BTC are those without a physical presence (online). This is normal, since Bitcoin is still in the early days. Once the Lightning Network takes off, we might see BTC being accepted almost everywhere (grocery stores, restaurants, gas stations, etc). Who knows what the future will bring to long-term BTC holders like me? Just my opinion