From a purely pragmatic standpoint, remember that in use a compressor, like all equipment, is going to be installed in a room to support some other process. These things can be big, and every square foot of floor space costs money to build, or you might be trying to fit the thing into the same...
A very useful analogy for thinking of electrical energy transfer is that of water flowing in pipes. Think of voltage as the water pressure in a pipe, and the electrical current as water flowing though the pipe. From experience you know that you can have water pressure in a pipe without having...