They are not just giving them out, they have put them in showbags for the kids doing the Milo T20 Blast - VERY hard to get as they have not been handed out on mass. I saw a box full - approx 10 - 15 bags at the first game, with 2 cards in each ( I was in the right place at the right time, as there was one bag spare and I asked if my son could have it ) otherwise I would have missed out.
At the second game I only saw 2 handed out.
The pre match function where they give away signed bats & other stuff, they actually gave away a full set signed by the whole squad!