snowdown chests...really? I'm feeling scamed

I don't tend to complain much at all, but just wondering, 3 of my friends who bought snow down chests got repeated charred maokai and obsidian malphs, I myself got 3 of charred and a malph, I know they stated you could get repeated shards but really? Do they have a fixed rate or something? Something smells fishy here, anyone else?