He also can’t get inside a Gen Z woman, but that’s never stopped him from obsessing.
Lucas gets fixated on things and places that reflect the fantasy version of himself that he wishes was true.
Because Lucas isn't young, and he desires young women, he tries to think of ways to present himself as being the positive alternative, and because the positive adjectives associated with older men are distinguished, sophisticated, mature, Lucas must be those things.
This is the only reason he fixated on those particular bars. Lucas is quite afraid of youth culture. He wouldn't fit in any better at a bar that caters to an older group of people, if such a thing is even possible, but he loves to think of himself as sophisticated, when in reality, Lucas is less mature than your average 16 year old guy who has an after-school job.
Lucas is literally just a whiny baby crying out for a titty.
Edit:
It's funny, Lucas mentions that he used to be into older women around the time he dated Suzanne, as if going after her was a conscious choice, rather than taking the only woman he could get.
But if there's any truth to this, it shows that Lucas, before EBT cards and social services, wanted to be taken care of above All Else. He was willing to temporarily put his pedophilic sexual fantasies on the back burner, and have sex with an older woman he wasn't attracted to, just to be guaranteed a roof and food.
At some point, Lucas realized that an EBT card and the largesse of the social system in a town like Spokane would fill all of his mommy needs, and he decided to pursue his genuine sexual desire, young girls.
Still, it's interesting to me that at one point Lucas was cynical and practical enough to pursue a woman only to the betterment of his status, much like he says about gold diggers. You could easily argue that Lucas was a gold-digging man, seeking a situation with a woman who would support him.
I mean, is that really such a stretch? That's exactly what he was doing.