The average dog is a nicer person than the average person
If Tarzan somehow manages to finish second, that will be the best three back-to-back runner-ups ever (Phillip, Coach, Tarzan).
And why the heck would Jay even call her a slacker? We've seen she does try hard in challenges and has proven to be good at puzzles, and she works around camp. Heck, I know I remember when they were supposed to go to TC, before the men's tribe gave up their immunity to go themselves, Sabrina was campaigning to keep Christina and vote out Alicia because Alicia was a jerk and did nothing, whereeas Christina worked hard around camp, something Chelsea (or was it Kim?) agreed with.
Honestly, I heart Christina, so I too wish we could get a clear reason on why these people don't trust or even like her, other than them being stupid jerks.