I haven't any Bitcoin url shortener recently, so I can't vouch for any of them. I can only suggest to look at Micro Earnings section here on Bitcointalk, I saw announcement of few shortlink websites. I also remember seing list of Bitcoin shortlink websites somewhere, but now I can't find link.
people barely trust obvious short links such as goo.gl and bit.ly because they are "hiding" the real URL and visiting random sites could be a disaster specially for bitcoiners who may leak their secret information and lose money if they get infected. they are never going to click an unknown looking URL that is also shortened.
if you are looking for ways to earn money, there are better ways.
You have good point, "clean" websites rarely shortlinks. Usually it's used by torrent websites, other kind of download websites, movies online. It's also often used to monetize faucets. Owners of such websites have to use shortlinks, because they don't have many options how to monetze their websites. They aren't accept to Google Adsense and other solid ad networks.