LeaverBuster should NAME users...
The logistically appropriate approach would be to ask, "Why not?".
Frankly, I'm with Voldymort. The better question would be to ask "why", not "why not".
But regardless, here's why not; because naming users under Low Priority Queue confers no genuine benefit to anyone for knowing that they're in LPQ, while simultaneously inhibiting those LPQ players from reforming. Because, as you said in response to zPOOPz asking what you would do if you saw an LPQ player in Champ Select;
Dodge the one time and come back later. You do know what "dodging" is, right?
This response to an LPQ player does not make the problem better; in fact, it exacerbates and perpetuates the problem that you're trying to tackle. And in dodging a match due to even one player under LPQ, you are becoming a part of the problem. It's pretty awful hypocritical that it's okay for you to dodge a match because of one player in LPQ while you absolutely abhor someone who's serving out their sentence for the same.
Add to that the fact that a person in LPQ has to play 5 consecutive matches without leaving a game to get out of LPQ - how are they going to go about doing that if every time they queue up, they can't get into a match because everyone sees they have LPQ and dodges?
At the end of the day, all having LPQ players named would do is tell you that x player is serving out their LPQ. It doesn't tell you why they have LPQ, it doesn't tell you anything about their likelihood of dodging the match or otherwise leaving - there's zero useful information given, and nothing good can come from having punished players publicly shamed like that.
support and jungle 
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