They choose to accept it for their goods and services.
This is why communist countries end up with empty shelves.
Bitcoin is the antidote to a government that threatens to tax your business out of existence.
The problem is that in this day and age corporations and governments are in many ways one and the same. Many of the legislation in countries is pushed by corporations. There are corporations for which Bitcoin is good news like IT ones I suppose but others that could see it as a threat like oil corporations who have most of their reserves in dollars. The fact that there's no central figure controlling the currency is a threat for many big companies because not having a central figure means not having something easy to control.