Aluminum is one of the most "recyclable" materials and aluminum cans are the most recycled consumer products in US. Used cans still have some economic value, and they can be recycled over and over again. There are economic and environmental benefits. In 2003, 54 billion cans were recycled in US.
But still, residual value per can is small. If you want to bring used cans to recycling center to get some money, or if you were to collect them for charity or fundraising, you would want to collect as many cans as possible - and effectively.
Storing as many cans as you can in a small space will really help, since it will increase the value per cubic yard and makes transportation a lot easier.
Aluminum cans can easily be smashed to almost flat. There are many "can smasher" offered in Japan.
Small tip to make small aluminum cans even smaller and increase their value.