Question About Very Tall Buildings / Skyscrapers

They don't. But large buildings have lots of people, to-ing and fro-ing throughout the day. The air loss from frequent door opening puts a strain on the building's heating and air-conditioning system. Revolving doors minimize that treated air loss.

And the security guards enjoy the games people play in them.

Plus they are more fun than normal doors you can spin in them.
Can you imagine Superman changing outfit througha normal door!!?

Thank you guys.