I'm definitely not a big fan of Cristina, but you have to be careful with what you hear about her. She has plenty of political enemies (especially in Clarin) who have connections and say nearly anything to tarnish her image - journalistic integrity isn't of the highest order here if you haven't noticed and who knows where the NYPost got their source. I would take this as pure gossip.
If it is true, it would be very hypocritical of her. I hope she will pay the import tax that everyone else is subject to! Though it is of course normal for Argentine's to load up their bags and catch up on shopping while overseas... it's much more expensive here!