Whether or not it's a net saving vs. transport costs really depends on where you happen to live.
I think the developer perspective can cloud the fact that the overwhelming majority just have a laptop and a place to put it for their "workspace".
There's little that is special about software development from that point of view.
"All those people" who are in cafes really are a tiny little fraction of workers, and most co-working spaces I've been to have a wide variety of proper office environments because unsurprisingly a lot of people need a proper environment to get work done.
Everyone whose house I've seen who works from home more than every now and again has had a dedicated space.
Wouldn't it make more sense for those who need/want a work area outside their apartment to get a co-working space?
Of course they can continue to spend that time doing the exact same walk if they want, no "make up some other way" necessary.
Those are just one or two of the social costs. How much does it cost in real money to relocate a family of 3 or 4?
People who live close to work in an expensive area have traded money for time. Higher salary; shorter commute. They may not have the resources to move.
IMO, that’s a strange definition of free.
"How much does it cost in real money to relocate a family of 3 or 4?"
Versus living in the aforementioned very expensive area? Seems like it would probably save money to move somewhere more affordable.