meh, urinals are less hassle. No doors, seats or toilet paper to get in the way.
And yes, I too have heard that pissing next to someone at a urinal does make men uncomfortable, though I think it might be more of a physical sub-conscious thing than a conscious thing most of the time.
A bit of 'hmm, I really needed to piss but it seems to be taking an extra few seconds to come out, hmm, i'm standing at a urinal with other men with my dick out and nothings happenni..... ahh there we go.'
I'm sure most guys know what that is like even if they won't admit it.