Look at the Hawks, Kings and Bruins who have probably been the best since 2010. They very rarely trade their picks, especially in a salary cap world. We don't develop any young players and are forced to trade for 3rd and 4th line players.
Those teams are competitive year after year and have a decent amount of prospects still coming up.
Chicago
2015 - 1st for Vermette
2015 - 2nd for Timonen
2014 - 2nd for Brisebois and Rundblad
2012 - 2nd and 3rd for Oduya
2011 - 2nd for Campoli
2010 - No trades with picks really.
Totals - 1 - 1st - 4 - 2nd - 1 - 3rd
So in the last five years Chicago has traded a 2nd round pick every season but two.
LA
2015 - 1st for Sekera
2014 - 2nd for Gaborik
2013 - Two 2nds for Regehr
2012 - 1st for Carter
2011 - 2nd for Richards
2011 - 1st for Penner
2010 - 3rd for Halpern
Totals - 3 - 1st - 4 - 2nd - 1 -3rd
So in the last five years LA has traded at least a 2nd or a 1st every year besides 2010 when they weren't really "contenders" yet.
Boston
2015 - Two 2nds for Connoly
2014 - 3rd for Meszaros
2013 - 2nd for Jagr
2012 - No trades with picks really
2011 - 1st and 2nd for Kaberle
2011 - 2nd for Kelly
2010 - 1st and 3rd for Horton / Campbell
2010 - 2nd for Seidenberg
Totals - 2 - 1st - 6 2nd - 2 3rd
So Boston hasn't really traded a lot of picks, but have at least given up a 2nd in every other year.
Penguins
2015 - 2nd for Winnik
2015 - 1st for Perron
2014 - 3rd for Stempinak
2014 - 3rd for Goc
2013 - 1st for Iginla
2013 - Two 2nds for Murray
2012 - No trades with picks really
2011 - No trades with picks really
2010 - 3rd for rights to Hamhuis
2010 - 2nd for Leopold
Total - 2 - 1st - 4 - 2nds - 3 - 3rds
Doesn't look as bad as people want to make it. The issue our team has had is not "trading" picks. It is the fact we don't move players like Orpik or Nisky last year when we need to restock on picks. That is the downfall of the Penguins, not the fact we are "trading" picks.