I don't know where you got this idea, the NRQZ encompasses a huge area and people most definitely do have microwave ovens.

https://en.wikipedia.org/wiki/United_States_National_Radio_Q...

You think that nobody in a city the size of Harrisonburg VA has a microwave?

https://en.wikipedia.org/wiki/Harrisonburg,_Virginia

It's within a 1 mile radius of the radio astronomy dish that petrol engined cars (spark plugs) and emitters like microwaves are banned.

You can install licensed point to point microwave radio and VHF/UHF radio systems, etc in the NRQZ, you just need to go through a coordination process.

https://science.nrao.edu/facilities/gbt/interference-protect...