That is the point. It's a way to get the value of a service you don't like, while signaling to everyone that you're too virtuous to use the service you're getting value out of.

I prefer not to share links that require the people receiving the link to create an account to read the content and it's replies or post to such websites for that matter. That's basic netiquette.

So that's supposed to be the motive? Frankly I think most users just see it as a path of least resistance to a tweet. You guys really aren't familiar with this Internet thing.