(Now occasionally I do get some pilots that find the most ridiculous things. I attribute that to not wanting to fly.)
We reffer to this as "PCF". It is sometimes a major factor in determining if the pilot is motivated to take the plane or be a stick in the mud on a little issue. "PCF" or Pilots Car Factor gives you an idea on wheather the pilot is going home to his car "motivated". Or heading away from car/home "unmotivated to down right kicking and screaming". Ive also seen plenty of pilots who were just crabby - didn't like the layover hotel/food/transportation didn't get any from flight attendant and they are looking for someone to unload on.