To irritate you. ;-)Actually it makes them feel good that they are now "connected" somehow.

An uninsured worker that gets hurt on your property or a contractor digging up a gas line with a back hoe or disposing of toxic chemicals like paint or solvents into an environmentally sensitive area can result in a huge liability that can easily exceed the value of the property.

Again, aside from the idea of water being wasted as a source of irritation for me, the raw cost of it from a business point of view is no matter, as long as you can roll it into appropriate rent.

It can create a toxic environment for the other tenants in the building as well. 

I've heard about Goldman Sachs and other large institutions buying thousands of loans and holding on to them (punishment for the its role in packaging and selling toxic mortgage-backed securities in the housing meltdown).

Both non-toxic common varieties. 

You want to make sure he pays his bills on time, just like a regular tenant, and that he won't trash the garage or store toxic waste there.

They are out of Iceland and the barrier in language/verbiage was a constant source of irritation and problems.

There are quite a few towns that might be toxic to invest as they are losing population over the next 20 years.  

Is it just the marketing that irritates these people?