The reason it’s there is to guard against a different, even worse abuse of the system.
Back when RDF was first introduced, tanks would stay afk and demand to be kicked anytime they got a dungeon they didn’t enjoy running or players they felt were too badly geared. The reason they did this is because they could then instantly requeue.
To prevent this behavior the debuff was added. It has this effect, but the other scenario is worse.
Blizzard doesn’t police use of the LFD kick, and there is no section in the TOS covering it. Any reason 3 other people agree on, including “this player’s gear is too low”, “this player needs the same loot as my friend” or even “this player’s choice of tabard or haircut is aesthethically unpleasing to me” is a valid reason to kick anyone from RDF.