I have 4 water butts. 1 very big one near the back door that is filled by the main drainpipe from the roof. That one has a tight fitting lid, and is raised on a stand so that watering cans fit underneath the tap down the bottom of the butt. I use it to fill the watering can I use for the indoor plants, some of them are a bit fussy about tap water, and for watering all the troughs and containers near the back of the house. (I also have a stash of water purifying tablets, and come the zombie apocalypse, that is the butt I'll be getting my drinking water from.)
The second butt is the size of a lidless dustbin, and is under a rain chain, made from little iron buckets, that channels water down from the flat roof at the far end of the kitchen extension. I enjoy watching the water cascading down the chain of buckets on rainy days, and find it much quicker and easier to fill watering cans by dipping them into the butt, compared to waiting for them to fill up under the tap on the bigger water butt. Sometimes, when I've been a bit lazy with the watering and the hanging baskets have dried out I unhook them and drown them in the butt until they stop bubbling, by which time the compost is properly wet again and it is a lot harder to lift them back onto their hangers. The disadvantage of an open butt is that mozzies are drawn to the open water in springtime, and lay eggs which hatch into wriggly larvae. I keep an eye on it and remember to tip it over every now and again, using the hosepipe to flush out the mosquito larvae onto the ground. Then I go indoors and leave them to the birds, who have learnt to expect a feast when they see me emptying the butt.
The other two small butts are on either side of the greenhouse, catching the water that runs off each side of the roof. They are open topped too, so after watering I dip the empty watering cans into the butts and then leave the filled cans sitting in the greenhouse till the next day, so the water in the cans is the same temperature as the rest of the greenhouse when I waddle down to do the watering the next day. Those small narrow butts only hold enough water to keep the greenhouse going for a week, so if it doesn't rain I top them up with the hosepipe. It's still more convenient to only drag the hosepipe down there once a week compared to having to do it every day, and I wash out any mosquito larvae before filling them up again.
I don't remember there being a hosepipe ban here, but we get loads of rain and the water supply is metered, so it makes sense to store the free stuff.