Don't Covet

 We just finished a sermon series about the 10 commandments this morning with "don't covet", and it raised a question in my mind.  

Is there not a point where "pay your fair share" becomes simply coveting what others posses?   Does the fact that the covetousness is for some amorphous "greater good" , somehow make it acceptable?  

Finally does the very concept of "don't covet" that which belongs to your neighbor at least suggest the notion of private property?     I get that everything belongs to YHWH and that we are stewards of what He gives us, but this commandment seems to suggest that what we steward for YHWH is (in a sense) ours and should be protected from others.