When I drive around town, I like stopping to let people across the road, it seems like a nice, obvious thing to do.
Similarly, I very much like to be let across the road by a thoughtful driver when I am the pedestrian. But when somebody is kind enough to let me across, I feel the very least I can do (to return the favour) is to pick up my feet and get across the road with some level of urgency.
Unfortunately this doesn't seem to be the case for others when I am in the driving seat. My little wave across the road seems, more often that not, to be a cue for people to lose the propelling power of their legs. Sometimes the 'crossee' seems to spot an opportunity to pause and contemplate the universe. Whatever the reason, many of the bods I wave across do so with something less than grateful expedition.
This is true from everyone from Grannys to Juniors. Kids (God!) never has acne moved so slow as when it's in front of my car.
Please, if someone is thoughtful enough to let you across the road, do as Eliza Dolittle famously suggested...
MOVE YER BLEEDIN' ARSE.