I tend to think of Mero craft as being more like the pirate ships of the open sea's every so often they hole up in a secluded area and have a few small safe harbours rather than one central meeting area. As far as socialising and planning the average Mero probably spends a lot more time jacked in than their counterparts, luxuriating in the oppertunity presented by being a superpowered redpill

Since Redpills already show as contraband signals, wouldn't it be safe to assume that the wireless connection operatives use to access the Matrix can come from anywhere? I'd second that Merv ships would have to be pirated vessels or rebuilt ones, or perhaps Merovingian operatives make use of hoverbarges. Also, what's to keep a Machine operative from accessing Zion's mainframe?

Up until recently, with the breaking of the truce, I'd imagine that alot of humans - regardless of alignment - would reside within Zion's walls during downtime. Of course, those who are open about their alignment AGAINST Zion operatives might be kicked out of the safety of Zion's walls.