The system shown here by James Yaeger is similar to what we use (big black duffel bags at the moment for us...the rolling REI bags would be preferable) to contain, organize and conceal gear. Lets you carry potentially eyebrow raising stuff in a totally innocuous manner. I mean, everyone has big bags for travel, right?
In military circles, this would be termed a loadout bag - one giant bag where you chuck all your mission gear to transit. Military dudes would obviously not care about the low profile look, but same general idea here.
This kind of system also gives you some spare cubic inches for useful, but not critical stuff. Clothes, toiletries, comfort items, more consumables, redundant gear, etc. If you've gotta leave the pavement behind, then that stuff probably gets ditched - but at that point, oh well.
Lots of bags to choose from out there, too - from duffels to rolling bags to backpacks to various hybrids (duffel/backpacks!) - to fit your mission. If you like luggage, eBags is the best place I've found - and their house brand is really good for the price. For cheap, durable and functional, the Northstar brand on Amazon are a pretty good choice for big, simple duffels.