How's that work when you want to use some? Do you have a giant chunk of frozen meat you have to get smaller, more usable pieces from? Do you thaw it enough to cut then put the rest back? I can't picture how this works.
Typically when you buy a large fraction of a cow, the butcher will process it into a bunch of different cuts, I.e. ribeye, flank, chuck, tenderloin, etc. the cuts are usually single-serving, except if you want to keep the tenderloin whole or something. You also get a bunch of hamburger patties or ground beef. Point is, you get all the meat pre-cut before your freeze, so you can use only what you need at any given time.
There are a lot of other issues with their "buy a cow" idea.