It's indeed a different scenario if we compare it with other casinos where they ask their users to wager with their official games only. 
Are you sure about it? More than 90% of the casino doesn't count the wager of in-house games if the user takes any bonus (like deposit bonus). There is nothing exceptional on MoonClub .@OP, You need to be more active here as your casino is new. You have to clarify the inquiries here to clear the doubts. Your casino has a Curacao license, but most of the clauses of your casino rules are copied from other casino.
Yes it is normal in most casino where in-house games does not contribute toward wagering requirement when player take a bonus such as deposit bonus. The question here is about the above quoted term "not allowed to wager", does it mean what players who take a bonus will be banned if they play in house game? What "not allowed" means here? If it works like in other casino, I think the best terms should be "in-house game does not contribute towards wagering requirement". Just a bit strange if players are not allowed to wager in some games while having an active bonus.