Fair enough. My only response would be that ATT/WB are only motivated by profit. They aren't motivated by upsetting comic book fans or just publishing their own favorite character. They're publishing what sells. And if it's mostly Batman books you see at 1/2 Price, I'd imagine that might have something to do with there being so many of them. (There are not very many Legion books to even put in those bins, for example.)
Batman will be oversaturated when his comics stop selling so well. If that happens, the big bosses will adjust in a New York minute by reducing The Batman titles they publish.
Again, this is only to do with profit margins, which has been the case with comic books going back to their very beginnings. Read Morrison's Supergods and you'll see that that's indisputably the case. You can also read the oral history on The DC Implosion to see what happened when DC tried to expand its line exponentially to find and feature new comics. What happened then is what's happening now. But both books demonstrate that the comics industry has always responded most to profit margins, and never to which characters hardcore comics fans want to read.
If those characters sold, you'd see a lot more books featuring them.
Batman has always been popular, on par with Superman. But it was after the 1989 Batman movie and the explosion of Batman fans that resulted from that that DC started publishing so much Batman. Why? It's not because he's a great character (though he is), it's only about profits and the survival of the industry, which has been at issue since WWII.
We're in an echo chamber here, a forum dominated by comic book super fans, and opinions here reflect that. The average audience for comic books doesn't even know about such forums because they don't care about them. And that audience is constantly shrinking. It doesn't matter what we'd prefer or what creators or editors do, it's a matter of what casual fans buy and that's all it's a matter of.