The question might not be "how often", but "how willing" are you to spend Bitcoin more often (If that is possible) in your area. Since most of the people in crypto space are keeping every fraction of Btc to save for the next bullrun. To make things short, most people treat Bitcoin as a store of value more than a currency.

We have not much of an option here in the 3rd world county, especially in a rural places like where I am currently situated to pay something in Btc simply because you can't barely find someone accepting Btc. However, I have to agree with you that because there is no writing about a merchant not accepting Bitcoin doesn't mean they automatically rejects Bitcoin as payment, we could always ask.