In the DC and Marvel universes, alien invasions seem to happen almost weekly, super-villains have impossible technology, which they use to rob banks, and genius super-heroes invent equally impossible technologies to combat them.
And yet somehow, nobody seems to come up with practical applications of said technologies for the average consumer.
Stilt-Man's outfit could be sold to, say window washing companies, first responders, and more. Tony Stark's Arc Reactors should be powering buildings independently of the power grid. I'm just scratching the surface.
Now out of universe, the main reason they don't have anti-grav, lightspeed spaceflight, et al, available to the public is because it would make the world so advanced, and so different from the real world of the reader that they might find it harder to identify with it, and may stop reading. The book would become more like a sci-fi comic, and less than simply a super-hero comic.
But with the clear existence of this tech, what are some (interesting) ways that government or business might ask for, or even demand, the tech for the people? And what are some reasons the heroes (or villains) might demur?
One reason I could envision is they don't want the tech getting out there, for fear it'll be hacked, and their powers and abilities could be rendered vulnerable. That's just an off the cuff idea.
There's been occasional stories about this.
The Armor Wars storylines in Iron Man deal with Stark's tech being used in a variety of other people's (good and bad) powered suits, and his attempts to stop them.
JMS had a scene in Fantastic Four where they needed some money. He scribbled a formula on a piece of paper, said it was for a new acne medication - told them to call Revlon and say he'll take thirty million plus royalties for it.
Dan Slott did a series of stories where Spider-Man adapts his tech for the consumer market, quite profitably. The polymers of his webbing becomes new materials for motorcycle helmets, Spider-Tracer tech becomes an improvement to wireless earphones, etc.
Heck, In Independence Day II, Earth reverse-engineers and adapts the alien technology, creating not only powerful new weapons, but many changes to society. But as mentioned, that's a Sci-Fi story, so such societal changes would be more readily accepted by the reader/viewer
So perhaps a sub-question is, in addition to ideas as to how it would be handled, what are some favorite stories where it WAS addressed?
(flipped a coin as to whether this fit more here as in Sci-Fi and Fantasy - seemed more germane here since it's more about the storytelling aspect than in-universe "explanations")
Postscript - A very germane TVTropes entry has been pointed out in the comments - Reed Richards is Useless.