Part of the reason is that there are many good tactically-oriented manufactuers that don't offer their products in non-tactical colors. I've commented more than once to Countycomm about that. Coyote, OD, and black are the least "tacticool" you can sometimes get.

Yes, of course there are great civilian manfacturers too. I LOVE Mtn Hardwear, TNF, Marmot, etc. And I use them A LOT when camping. But, for something that I'll most likely use only infrequently, it's often cheaper, and in some ways more durable, to go with military surplus or similar. I'm not about to drop $150 on an Arcteryx backpack that's sitting in my basement for 5 years, when a $40 USGI alice pack is bigger, cheaper, and not too painful to replace if something happens. My Arcteryx, though, leans up on it, and it's filled with more used stuff.

If I want to be seen, I'm not counting on my backpack to do it. My orange stocking cap, or rain slicker, or blue tarp, is going to be used for that much more easily.

Besides, if it's ever time for "scrounger mode," I'd like the option of dropping my bag in a patch of brush in a city park and being able to retrieve it later. Kind of hard to do with my bright blue Arcteryx!