I had a job selling newspaper subscriptions door-to-door when I was young (like 15ish), the thing I noticed was that grumpy people are normally in the mid-30s to mid-50s range.
I worked that job for 9 months (it was awful) and I would talk to upwards of 30 people a night, 4-5 nights a week. What I noticed (and this is all anecdotal), 30's-mid 40's women were always very polite and would make time if they had it, men in that range were extremely rude and had little patience for a solicitor. Mid-40's to 60 the roles reversed, women would be a lot ruder, but the men would be nicer and almost had an appreciation that I was hustling and would make some time for me.
Over 60, most women and men were pretty laid back and accommodating if they had the time.