Bike racks? What are those?
Seriously though, in the rural towns in my area there are literally NO racks, and we must just lock to odd things like trees , lamp posts, and stair railings, etc. So we need a 6' cable to go around stuff like that. I have a 3/8" cable with integrated lock. It does take up some space in my saddle bag but what the heck.
If I lived in a big city like NYC or Chicago though, I'd have WAY more major locks than that.
Campuses are another stealing hot spot.

Better safe than sorry- better a bigger lock than you need than a smaller lock than you need.