They weren't penalties - they were legal hits. The refs called nothing on Tkachuk, the league also reviewed and they agreed the hits were legal. So do you mean that they should have made something up to call on Tkachuk, to ensure that wing nut Kassian doesn't go bat poop crazy on him?? Yeah - that's fair!
Because the refs called nothing ==== no penalty ever happened? LOL.
I saw ... late hit... elbow... hit from behind... charging. Take your pick.
League protects the refs.
Maybe you should also go read Paul Stuarts blog and edumacate urself.
And talking about "legal"... the League ruled Matt Cooke's hit on Marc Savard as "legal". I suppose you think there was nothing wrong with that... right?