Some actions are legal and still reprehensible. You won't get punished by the state or the police but that doesn't protect you from scorn, disdain, harsh comments and insults. Actions have consequences.
I guess some people need it spelled out. I think when I was young I also needed somebody to tell me because when I grew I, I thought that the state is great, the law is great, and we're all good people. But morality, justice and the law are not the same. The law only concerns the things were the state will come and impose fines and punishment. Justice is the thing we aspire to (but which the state often cannot deliver). And the moral good goes further than that.
To be morally good or bad is different from being just or unjust and that is different from something being legal or illegal.
So please, when people say that something is reprehensible they usually don't care whether it was legal or not because they aren't going to call the cops. It's an occasion to be happy for just got being called names, for only getting demeaned and ridiculed, for just getting inundated with mails and complaints. Because when the cops show up and take your stuff, when you get those invitations to show up in court, when the bills start coming, then it's worse. Much worse.