US Postal Service Protected by Federal Law?

I should not be surprised or even the least bit upset because I knew there was a law about putting fliers and other stuff in someones mailbox.  I was not aware however, of just how all encompassing the law really is.  Even if the United States Postal Service (which is not a government agency) goes broke, can't keep it's business running and folds up like a withering flower on a hot day, you can still face a fine for using those mailboxes.  (Read more here)

This law also applies to any box attached to your home that the post office can deliver to.  The only loophole is the slot in your door.  This law was passed in the 1930s and passed again in the 1980s.

Are we missing something here in regards to personal freedom?  If I put a planter with a lid on it at my curb and someone puts their flyer in it, will that person be up for a possible 5,000 dollar fine, just because the postal service could also use it?  what about a breadbox attached to my house, would that also earn a fine?

As home owners we pay exorbitant fees and taxes to own our home,  repeat OWN our home.  Ownership should allow us the freedom to use boxes attached to our homes as we choose to see fit.  

I sure hope that if the postal service fails to float anymore that this law will be revoked.