Whilst I've never seen something so brazen before, I'm not surprised and wouldn't be so quick to blame "eastern Europeans". I've encountered plenty of anglers, of all kinds, over the years that would cheerfully knock a pike on the head, given half a chance. Things have changed over time but if you believe that every one of the pike killers from years past have changed their attitude, you're only kidding yourself. They may not be vocal any longer, they now know that they are in the minority and would be castigated for their views should they voice them. However, they still retain those views.
Same goes for the badger baiters, hare coursers etc etc. They are still out there if you know where to look. Perversely, it's often urban areas where such folks come from:confused:. They've not changed one jot despite knowing that the vast majority and the law are against them.