questions for google streak users

I've recently noticed that the links in my last several months of sent messages all start with "streaklinks.com" 

I most certainly did not include that part when I formatted those hyperlinks.   

Streak has decided to add that part on its own.   Does anyone know why?

Also, seeing as how it's now pretty obvious I'm a Streak user to anyone who reads a hyperlinked email from me ... Do people tend to look unfavorably upon Streak users? (there is, i suppose, something a little bit stalkish about wanting to know if, when and where someone has checked your email message)