...who are all working in their offices, because most of them aren't programmers.

Despite being rather introverted, I have a fairly active social life outside of work. Nothing against my coworkers, but I would work from home full time if I could.

When talking to companies I am always surprised by how many are not friendly to fully remote employees, even ones who work on online collaborative tools.

I think this is where a lot of remote workers fail to adapt, myself included for a few years. Remote working has its disadvantages but it's not unsolvable. Nowadays, I make it a point to go to local meetups on a consistent basis, which actually allowed me access to social networks far outside the limited network within my company.

What's nice is that it forced me to learn how to make friends outside of typical environments (work, school). It was far easier than I realized, and now I regret not doing it earlier in my life.

Meetups are awesome.

I highly recommend board game meetups! There are lots programming related meetups as well.