[moonboots]

These link modifications increase privacy by hiding the referer from the destination page [1].

[1] http://www.gabrielweinberg.com/blog/2010/05/duck-duck-go-sea...

[glimcat]

Also, leaving the clean link isn't trickery. It's usability.

I can do "right click + copy link" on DuckDuckGo and get a clean copy of the link. That isn't the case on Google.