Yes, and before you know it, it is mandatory. Then the track all your purchases, patterns of buying.
You think they don't do this already with your credit card? My son bought a scope and mount online while visiting here, and first thing he knows, bank security calls him, it is not his usual pattern of buying, they want to know if that was him or not.
Well, if your own bank is tracking your credit card buying, where and what, soon the government could be doing the same. Then with a universal identifier for each and every purchase... well, you figure it out.
Then look at Chicago Mayor Daley's Nazis cross referencing FOID cards, gun registrations, etc.
"Just because you're paranoid, it doesn't mean they aren't out to get you."