There never needs to be a reason to ink a place up. Gotta cover the turf and claim it.

Mammon will find that the ink is thicker than water, more like paint in consistency and opaqueness. The ink wants to glob together rather than spread thinly. The ink sticks easily to many things in many orientations, yet there are some surfaces it just drips off of instead of sticking. Metal, glass, and tarp are among some of the materials it won't stick to.

It still thin enough to shoot out of various weapons and allows for Inklings to swim through it... though the latter might be part of the Inkling physiology.