i think now many games like this , but yet such games are fun to play and yes you always should read rules lol , bombs are hidden in rules 
Like the rule of not returning sent funds after the round has ended. I'm pretty sure they could have easily programmed a script to reverse transactions to those addresses after games are finnished but probably they're more comfortable with outright theft.
It's just because of the technical difficulty - it would require to check periodically all 1700+ addresses of finished rounds for payments accidentaly sent to them.
However, you can ask me anytime to refund any payments - just send me your transaction ID and I send you bitcoins back manually.