I don't collect water for them, but they like to drink from the pools of rain water the collect everywhere for over half the year under the rain in the PNW. Granted, they also like to drink the dirty floor water that pools up on the floor instead of the clean water in the water pans. Maybe it has more flavor? LOL
Yes, we use it all the time. We collect it in barrels and use about 1 barrel every 2 days or so. It doesn't get stale enough they won't drink it. They actually like it better because our faucet water is full of chlorine and other chemicals. We empty our barrels about once a month and clean out the bottoms.
We have a 300 gallon tank ready to go in the run we are building to collect rainwater from the roof of the coop and run. We will use what is collected for the chickens.
There will be times I may have to open the faucet and let it empty into my garden if we have storms coming...would rather it not overflow in the run.
We do not get much annual rainfall but prefer our chickens not drink our city water...city sends a letter monthly telling people they can get cancer from drinking the water. Don't think it is safe for my girls!
We are using water from the water store until we can redo our kitchen and put in water filtering system.
Every chance I get. In fact I keep a 50 gallon trash can sitting under the eaves to catch water....after a few days if I don't use it all, I will throw it out, I don't want mosquitoes laying larvae in it.