Did you look at the team with the level one cards and see how many "Champion points" they had? Was it a team that had reached the champion level of rewards and has decided to back down the chain to make for easier daily quest wins or to re-learn how to play in lower levels because of the Tournaments? Often times that lower level deck that wins is from some one with a few championship points. meaning they reached the championship level and have likely moved cards around to build another account to championship level.

Steem Monsters needs to change the Season rewards to be the same as the daily rewards. Where you finish the season is what you season rewards are based on. So if you reached Championship Level 1, and end the season at gold 2 level your season rewards are 40 cards not 150 cards.