Wow, -1. I know I was being a bit snarky. But the definition of "commercial use" is horribly ambiguous, with basically no broad legally defined meaning.

If viewing ads on Google wasn't a commercial use I could hardly imagine anything else being one... but presumably they don't intend to reject commercial uses that make them money.

The whole idea about rejecting commercial uses is wrong-headed. It presumes that you can draw a bright line between someones activities being commercial or not. Really, just like the no-servers prohibition this is a frivolous field of use restriction which serves to act as an excuse for arbitrary enforcement.