I don't really care about gear color to be honest. I bought a tangerine-yellow Osprey Stratos 32 backpack as a daypack and for search and rescue mostly because I liked it's features.

I use a Black Diamond Bullet 16 which is black, this is my summit pack/short hike pack. Bought it because is was rugged but still lightweight.

I use a blue Arc'teryx Bora 50 pack for much longer hikes, bushwhacking or overnights. Got it super cheap off a classifieds site. It's blue.

My first LARGE pack was a dark green 70-liter Karrimor pack, I got it during a clearance deal but I harly use it.

So my purchases usually depend on :

1) intended use
2) price
3) closet space