After seeing a rear wheel of a bike that enables the rider to choose between fixed gear & freewheeling, I've been trying to figure this out.

The pedals of a fixed-gear bicycle revolve whenever the rear wheel turns; coasting is impossible but you could brake like a coaster brake, right?

So I'm thinking that a real purist with a freewheel wouldn't have any brakes. that they'd have to do a Flintstone stop

Then I remembered that this bike did have brakes.

What a dolt. At least I figured it out.
Go ahead. Have a laugh at me. I did.

But I still wonder why anyone would choose to ride a fixed gear?