I don't know, what I've mostly seen the VN regulars do in the five years I've been here is wish a lad well when he chooses to transfer. Sure, there will be one or two who comment about the player being recruited over, but the vast majority are wishing the fella luck at his next stop.
First one I recall was Vic Wharton to Cal. Also Drew Richmond to USC. There were others, of course, just can't recall the names off the top of my head. Largely polite farewells, each time.
That's how it has seemed to me, anyway. Don't think all fan bases are the same in this regard, after all.