I was driving through Montrose and have noticed on multiple occasions that buses will drive in the middle of the two lane street. Is this normal/allowed?

I was driving through Montrose and have noticed on multiple occasions that buses will drive in the middle of a two lane street. While I understand the streets here are a narrow, a whole separate issue being this cities infrastructure, it holds up traffic big time. Anytime I’m behind a bus it’s a whole ordeal as if the road is not being shared with the rest of the city. It could be that it is allowed I was just curious considering driving here is equivalent to fighting for your life. (: