I used to live in Maryland, and I agree about a rain barrel there not being worth it. But since I moved to the desert southwest I have a different perspective. Water is our most expensive utility. New businesses are required by law in my town to harvest rainwater. The day could come when there is not enough water to meet the population's needs all throughout the southwest. If the Colorado River dries up, cities like Phoenix, Tucson, LA, and Vegas are screwed. So, everyone here needs to do what they can. Although it rarely rains, when it does, it rains HARD so you can easily fill a barrel. So, at least, in southern Arizona, it makes a lot more sense than it does in Maryland.