Not abusive parenting, just a very unlucky run; remember Emmett illustrated a whole string of unfortunate events that they ended up being entirely blamed for mainly by dint of being the last one on the scene when the authorities arrived, because of course all the other alleged actors were safely tucked up in bed at the time, even at midday? Then they further implied that the selection provided was but the tip of the iceberg?
So yeah a whole string of not being believed, combined with a sudden move *to a completely different country* (which children are frequently wont to internalise as their fault somehow) has probably distorted poor Emmet’s view of how actions, consequences, blame, and punishment flow into each other. At least in their specific vicinity anyway.