They are almost all from Germany, containing 0,33 l, so maybe that explains the difference?
And they are almost all "special event" cans, like olympic games, soccer teams etc.

coca cola can collectors ??? daaamn

Almost all packaging has gotten smaller in grocery stores over the last few years as companies try to keep their prices from going up by offering slightly less for the same or a slight price increase.

#1 looks more like 60's / 70's.