Larry Niven's 1970s stories about "corpsicles" discuss a couple situations in which cryonics patients might be stripped of legal rights and mistreated after death. Beware of fictional evidence, and all that.
My personal con re: cryonics actually comes from the opposite direction, though. I like living in part because I can do (small) things which improve the world and because my mind is relatively unique. But a world in which society has a combination of technology, wealth and altruism sufficient for reviving cryonics patients en masse is less likely to need me to help it or to bolster my mental demographic. Unless I come into unexpected wealth, I'd prefer to spend discretionary money on things that improve the odds of creating such a world (savings for emergencies and my kids' education, charities, "buying" free time for less-remunerated research, etc) rather than on buying a ticket just to enjoy it after it's here.
In considering the pros and cons of cryonics, has anyone addressed the possibility of being revived in an unpleasant future, for instance as a "torture the infidel" exhibit in a theme park of a theocratic state? I had some thoughts on the issue but figured I would see what else has been written previously.