Boy flung a open beer can at me and my dog infront of maliveld

About 15 minutes back a group of Dutch teenagers were on their bikes were passing infront of paviljoen maliveld. And while I was minding my own business while walking my dog, a boy riding one of the bikes flung an almost full open can of beer at us. I shouted at them but they didn’t seem to care.
I got shit scared about my dog and don’t know if the can hit him and if any beer spluttered on him.

What the hell is this? Shocked.