Indeed, the Buffalo Sabres had placed their 11th overall pick on the market, reportedly targeting Martin Necas. However, it seems they've either changed their minds or that wasn't the case, as the transaction only involves draft picks.
This is the price to pay for moving up, and if Kent Hughes wants to do the same with his 26th overall pick, he'll likely have to pay even more to secure a top 15 pick.
It's known that the Canadiens' GM is keen on Cole Eiserman, the top goal scorer of the draft class, expected to go between picks 10 and 15.