Some of our table's players have dived right in and detailed their lifestyle, while others aren't too bothered. They have a shared warehouse, which is mainly a drone store, so some flop there as well. I guess it's something for the players to customise for their characters. Where they live has come up in-game a few times (like when the mafia came round and tried to petrol bomb them), and we actually spent quite a bit of a session with the runners just cruising round Seattle looking for a group base.
Our table's runners do spend quite a bit of time running around doing non-run roleplaying, and it can be quite entertaining. We have one runner who is trying to join Club 77 to gain influence, another owns a burlesque nightclub but has just kicked a severe alcohol addiction, and another is trying to kitbash a VTOL, so they all have reasons to go mooching round the sprawl chatting to folks. I've also got them to outline backgrounds, eg. where they were born and raised, where are their parents, brothers, sisters, etc. are now, so family can become involved as well.
On critical glitch podcast, interviewing Bull the ork decker, he was telling of when they first started playing shadowrun, of how much of their time was spent just roleplaying their characters outside of runs, even getting the call during a run, that his wife was in labour. On the arcology podcast, the characters sometimes go shopping for drones, etc. and once went on a run to rob Home Depot to get construction equipment to build their base. I guess this could get kind of exasperating for some GMs, but I do really enjoy it.