JVC, we need to compare apples with apples. For arguments sake let's say the momentum of the beer can was the same as the paper roll (it wasn't because the roll apparently weighs ~50 grams, while even at half full, that beer can is ~250 grams. So at the same throwing speed, at best the roll is 20% the momentum). The difference was that Ivic was actually looked at by the stadium doctor before being taken out by medical staff. Olympiakos refused medical inspection from the stadium doctor and basically snuck out with a private car. That makes the injury seem even more suspicious. If you are injured enough that you need to go to hospital, do you really refuse medical help at the time of the injury? Again, I bring the North American mentality where all head injuries immediately go through concussion protocol at the stadium.
I still think it was pathetic that he was escorted in a wheel chair. Did the stadium doctor actually say he wasn't ok to continue? That's where the main difference of the two incidents need to be looked at.
What happened with Savvidis was crossing the line. But lost in the gun, which no one saw until minutes after he was off the field, was the fact that PAOK scored a goal. We can debate whether it was offside or onside until we are blue in the face, and we will never have the right answer. The issue is that the ruling on the field was initially "Goal", based on the ref signalling a goal, and the assistant not raising his flag, and even motioning to centre of the pitch. Heck even the keeper who was the one apparently obstructed, didn't even complain. Then AEK players swarm the assistant, and after a few minutes, the ruling on the field is changed.
The events that followed are a boil over of the previous three weeks circus. Actually, you can even argue that it was a boil over of the 50 year circus of Greek soccer. This is why we need to actually stop the league and have a proper inquiry to all the things that affect Greek soccer. Greece will win the World Cup before that ever happens.