It's kind to show patience towards those with disabilities.
Dave is waiting behind Phil, who is mentally disabled for his turn at the street parking pay station and Phil is taking a long time.
Dave wants to say something to Phil about how slow Phil is.
Dave tells Phil that he can help him figure out the screen if he's having a hard time.
Dave tells Phil to hurry up because he doesn't have all day and if Phil can't figure it out to move aside.
Phil is happy Dave will help and relieved his little struggle with the machine is over with.
Phil is stressed from the pressure and nervous about Dave standing behind him angry.