Sure, it's how I learn about most of the music and art-related events I go to. There's not really an equivalent platform to get that kind of info. It would have to be a mishmash of email newsletters and checking blogs, and even then some people only promote on Instagram because of it's market dominance.
I'm talking about people who use it on a personal basis. Yes my mum sends Instagram posts to market her embroidery company. I don't care about marketing posts.