It depends on a million things, of course if you live across the street from your office you're a special case. Most people have to spend at least a few hundred dollars a month commuting if they go into the office with fair frequency.
$4-5k/yr can get you a decent bit. Remote also means you don't need to live in the city, so that cost is easily offset by moving into a more affordable area.
Moving to a different town is a big disruption which at least i won't do just to be able to afford a big house. Not only do you lose the option to come in to the office (which is a good option to have even if you prefer home office most of the time); some people just prefer to live in big cities.
It's a lot cheaper in the long run than a commute, all things considered.