18,000 subscribed user accounts out of about 36,000,000. That's .05%, or 1 in 2,000. Except that it's localized in one subreddit that doesn't make the frontpage and is universally reviled on the rest of Reddit.

By all means, leave. People that will leave a public forum because "someone over there is someone I really, really don't like and that every else around me also thinks is vile, but who I am not forced to talk to at any point in time" are generally not valuable users in a forum that is dedicated to open discussion.

I'm not going to go to a pub full of rapists and pedophiles just because the local Linux User Group sets up shop at the corner table.

You might think that's a bad analogy, but that's the reputation Reddit has garnered and I don't think it's insane to not want to be associated with it.