The humble vending machine has been a stock environmental asset in video games for decades. You probably don't even notice it, past your token attempt to make it work every time you find it in a new game (shortly after checking to see if the toilets flush). But you should.
You see, far from being a simple block of stuff with which to fill a spare bit of corridor, the video game vending machine is a medium for vast swathes of eclectic design endeavours. Every one is a unique, individual little snowflake of coin-operated commerce, and each should be studied and valued for its own merits. That's what we're going to do here. Buckle up.