No matter what round, the Chicago Blackhawks’ organization always manages to find talent. Duncan Keith, Brandon Saad, and Alex DeBrincat were all drafted in the second round. Niklas Hjalmarsson was drafted in the fourth round and Andrew Shaw in the fifth round.
Chicago has a very good knack for finding talent, so I guess it makes sense that they would be willing to part with their first-round picks more often than other teams. Finding talented players, no matter the round, makes your first-round picks more expendable, or at the very least, easier to trade.
Feeling confident in your players and depth picks makes trading your first-round draft picks more probable.