NL300 game multi-way with overcalls

At my local casino, the full ring 300NL has a strange dynamic, and I am struggling to find a viable strategy. Pre-flop, if you bet less than $20, you tend to get 5 or 6 callers. This is especially true in late position, as the players look at their $3 limp as if it were gold coin to be salvaged at any cost. Thus, any sane pre-flop action will go 6-way up to 8-way to the flop. So, I tried to find the pain point that would at least set up some heads-up or 3-way action.

It seems that when I bet $20 or more, if it doesn't fold around, it manipulates the few callers to the top of their ranges. So, my choices are to either play 6-way to the flop all night, or go heads up vs. Aces or Kings. I think the players are trying to fit as many hands as possible into the session, and I can see why they might want to. Nevertheless, it is quite brutal being up against 5 callers playing ATC for $17 apiece with me holding KK on the button and having the EP callers donk-betting $50 into a 27Qr flop.

What the hell do you do in this game?

Also, forget barreling. They look you up with K3o on a AJT93 board.

What strategies should I employ in this type of game?

Raise bigger pre-flop, and don't assume people just play AA/KK. Don't bluff ever if they are looking you up with any piece, just bet all your hands for value.

if the table are loose, you tighten up