I recently shot a wedding with a buddy of mine where there were other hired professionals doing what they do: videographer, musicians, coordinators... you get the idea. My friend and I do our best to stay out of each other's shots, but just in case it's unavoidable we both wear formalwear so we can easily blend in as guests.
Let me start this off by saying that one of my biggest pet peeves is inconveniencing people, or being inconsiderate to those around me. I've always hated the idea of being a burden on others, and thus, I often go above and beyond to avoid being a nuisance to anyone around me.
As a result though, I also hate it when other people are inconsiderate around me, or to me directly. In my opinion it shows a serious level of self absorption that is often quite literally outright offensive.
All that said, as a photographer, it can be hard not to be invasive of people around you and thus this little pet peeve of mine can often be at odds with the job at hand.