Re instagram... people hashtag the **** out of things so more people see their photos and like them. The primary reason that anyone likes a photo, is so that the person they liked will follow them and like photos in return.
It's a circular thing to the point where famous instagrammers are both famous and rich because brands see likes as engagement... so they pay people to shill their brands. Which in turn sees their brands get more attention and likes.
In the beer world, people with big instagram followings get a lot of free stuff. In the food world, instagrammers get loads of free food and dinners. An insane amount. Both groups always post blindly positive "reviews" so brands love then.
I've been to dinners with "big" instagram food peeps. They are garbage people, in their 20s, who basically game the system for free stuff. The PR people know this, but they are bigger garbage people than the instagrammers so they don't care.
Instagram ******* sucks.
Edit: I use it sparingly because it does have some uses as a content creator and is kind of necessary. But I ******* hate it.