Let's see...
I walk very quickly, so if I'm with someone else who walks sometimes I won't think about it and I'll just go speeding off without them. Maybe the effect of too much walking with people playing in carts...
I'm not particularly patient with slow players, and if we have room in front and are being pushed from behind I'll start to ignore the honor on the tee and who's away as a not-so-subtle hint to get things moving along.
I plumb bob every first, and sometimes second putt -- I'm quick about it, do it before my turn where possible and otherwise don't mess around when putting, but its become ingrained as part of my routine even though half the time I'll disregard it anyway.
If someone calls me on the plumb bobbing that adds an extra two seconds to my putts and claims it slows play, I'll tell them about their annoying habits that slow play, just in the interest of fairness
If I'm having a particularly bad day, at some point I might just quit trying, and it is pretty obvious that I've quit caring about the results of my shots. Maybe it has to do with hitting all my shots without practice swings and not lining up my putts?
I refuse to watch other golfers swing. I watch the ball as it leaves their club, so I can help look for it, but you are wasting your breath if you ask me what you did wrong on that last shot!
If I end up playing with someone I find I don't like, I think my condolences for their bad luck are probably not all that sincere