The reason you don't get a reply (in the US anyways) is for legal reasons. If you say anything which could be even remotely (mis)interpreted as some sort of bias, your company could lose lots of money/time and potentially go bankrupt due to a discrimination lawsuit.
It's sadly safer to just not reject candidates at all. Don't hate the player, hate the game.
It's sadly safer to just not reject candidates at all. Don't hate the player, hate the game.