* What these students did or didn't do does not matter in this case.
* Harvard can withdraw the acceptance for anyone at any time for any reason.
We don't need to argue about privacy or free speech here. All we can argue about as a first point is if Harvard should have the ability to withdraw their acceptance or not.
It is unfortunate that they chose to share those memes on a Facebook group chat though, I think the debate is about how not "private" a lot of our "private" chats have become and how sometimes people are just not thinking about where there communications are stored enough. If they had printed pamphlets with the material and shared them with classmates I think the same consequences would have happened, but they would have had more time to stop themselves and think about what could go wrong. Now sending offensive jokes is easy and "private" channels are deceptively public.