Unable to leave random steam groups

Question

I have a huge list of steam groups I've never joined in my "Groups" tab of the "Friends" section of Steam. It looks like this:

Some of the games I own, some I had on my wishlist, some I've never heard of. The top two are the only ones I actually want to be in. When I click on the Arrow and then Leave this group, I only see this:

Those are the two groups I remember joining and want to be a part of. I tried to join and leave the group, but when I click on the Arrow and then View Group Profile, all I see on the side is this:

I don't see any option to join or leave the group.

When I go to my public profile, it says I'm only in two groups and doesn't mention these groups anywhere:

How do I get rid of these groups?

Answer 1

When you ask Steam to follow a game, you receive that game's announcements in your activity feed. Not explicitly mentioned, or at least not where I could find it, is that you also join that game's official group. When you stop following a game, you will automatically be removed from the group, meaning that any rewards or advantages that require you be a member will no longer be available.

Official groups are not counted in the number of groups you're a member of; this was already the case before the introduction of following games and the discovery queue.

You can leave such a group in two ways:

• Go to the game's store page and untick 'Following':

  

• Go to your game's community hub, and click the 'Stop Following' link near the top: