I don't think any normal people are advocating violence against him, and as for mindless yobs, well, every club has them, sadly. Will he get a ton of grief if he plays for Palace and continues to live in Brighton though? Yes, of course he will. But I doubt very much that will turn violent.
That still makes no sense. Using that logic, no club would ever be able to offer a player under contract a wage rise, which happens all the time - look at Rooney earlier this season.