Aluminium is very easily recycled to a very high degree of purity.
Mining aluminium is very expensive and uses an awful lot of energy.  Creating a tonne of aluminium from raw bauxite (aluminium ore) takes around five times as much energy as producing a tonne from recycled cans, there are lots of reasons for using recycled aluminium.
Recognise that the smallest amount of copper and tin can disturb the recycling of Aluminium (and steel).  It is very important that any components made of copper and tin can be easily removed by disassembly.  As little as 0.1% of these metals degrade steel scrap to be used only for specified casting qualities.