"The Batman" on Ice
I was reminded of that second example while watching this morning's new episode of The Batman. Entitled "Fire & Ice," it had Mr. Freeze and Firefly teaming up to freeze the city for some reason (if they ever provided a motivation, I missed it). Mr. Freeze steals some liquid nitrogen from Wayne Industries (something I'll get back to in a moment), and uses it in a giant cryo-cannon that his abilities will power. The whole set-up is in an underground chamber full of pipes that Freeze says provides heat to every building in Gotham. And Freeze proceeds to freeze all the people in every building by sending frigid air (or ice; it's sorta unclear) through those same pipes. Sure enough, the plan works, and we see a lot of people get frozen in ice.
In case you don't consider Freeze's word about the facility's function reliable, Batman himself settles that. He saves the day by flipping the switch on the facility's "boiler," which then pumps nice hot air throughout the city via the pipes, thawing all the innocents.
Apparently, the entire city of Gotham has central heating. Out where I live, we tend to heat our buildings with a little thing called 'natural gas.' Or 'electricity.' But in the Gotham City of "The Batman," they seem to be unfamiliar with those resources, so instead there's a giant underground boiler that heats the entire city. Does this also mean that Gotham also has a giant central air conditioner too? Or how about an aquarium-sized municipal hot water heater?
It's just a variation on the railway cheat. "Mr. Freeze needs to ice the entire city from a central location? Then let's say every building in Gotham is heated by a single massive boiler, and hope that no one realizes that makes no sense."
I also wanted to say a bit on the subject of liquid nitrogen. Freeze pulls a massive heist to steal a handful of canisters from a Wayne Industries laboratory, each of which held maybe a half-gallon of the liquified gas.
I wonder if the writer thinks liquid nitrogen is much harder to obtain than it really is. You can buy the stuff from a great many gas suppliers at relatively low cost. In fact, Freeze's only difficulty would be in finding a dealer interested in selling that small an amount of the gas. OK, it's not like he can stroll into a store and place an order, but there's very little point in breaking into a secure, high-rise building in the middle of the night when he could more easily rob a gas supplier or, better yet, just send Firefly to the store with a couple of bills. He might was well be robbing Wayne Industries to steal their supply of ink toner or propane.