I wouldn't say anything, obviously, but I definitely wouldn't be as comfortable with it as I would, say, a sneeze.

I'm sure my female coworkers wouldn't mind vigorous nutsack scratching out in the open for all to see would they? It also is a perfectly natural activity and often necessary.

But hey, I also get annoyed at people who chew loudly.

The dilemma boils down to: people often find people's bodily functions discomforting. Where is the line for propriety? We somewhat allow nose picking. We don't like butt scratching. Occasional burps are fine, loud farts are wrong. Pooping anywhere but the toilet is gross, peeing on the side of the road is sometimes okay. Eating in publi is fine, chewing with your mouth open is not. Somewhere on this spectrum is breast feeding and breast pumps.