Of course it's stupid to say that Pokemon is satanist and all that crap, but you have to look at this from nintendo's point of view. Their primary customers are kids, and most kids don't buy the games themselves, but their parents do it for them.
Now imagine there is a new hype saying pokemon worships the devil and all that, WE know it's bs, but parents would listen to this and maybe not buy the game for their children, which would mean less sales for Nintendo.
I have nothing against a Houndoom evolution itself, just forcing it to be #666 would be nonsense