I never ever water the grass either, just seems so wasteful. The only time I used a watering can for the planters is when fertilizing them once a week years ago. But with 30-40 planters, some taking as much as 2.5 gals of water, that got old fast. I've since hooked up a drip irrigation system to all the planters, and put a fertilizer unit in too, so I never have to do the endless watering cans again. I'm a lazy gardener wherever possible!
Oh and my watering nozzle is one of the long reach ones, 33", and with a movable head, so I could easily do the hanging baskets without getting water all over the place, myself included.