They are. All you have to do is scroll through the third round of every draft. Half the picks don't even make it to 100 NHL games. Maybe half of those who do are what anyone would call an average player or better.
Yeah, if you trade away all of your picks all of the time, it becomes a problem when you don't have any magic beans left, but this team spent almost the entire last decade collecting picks and prospects. They can afford to blow a pick or three to try to help things now.
This isn't very scientific, but I did a quick analysis of 3rd round picks from 2004-2013 (long enough for players drafted here to no longer be prospects):
Less than 30% of all 3rd round picks play 100 NHL games or more. Most of these end up being journeymen or depth players who aren't sure they'll even have a job after each offseason.
"Notable" picks here are players who became and still are "high-impact" players (top 6 F, top 4 D, #1G). Marchand and Letang are really the only notable skaters, with a handful of quality goalies that are typically voodoo picks (Quick, Bishop, Andersen, Murray, and a few others).