Because it is better to "serve" God without being his slave. It benefits you and him, it's a better relation.
Making you believe, he could, but he wants you to chose him freely.Why? Who does that benefit?
God could make you his b**ch but doesn't. He gave you your freedom so that everyday, every minute, every moment in your life you could choose to believe/follow/love/pray/thank him.
That's the point, isn't it? That every minute, every moment, you have to love god.....or else suffer.
Tell me something, Lukvance. Which is better? Being a slave without the slightest idea that you ARE a slave and without even the concept that slavery exists......or "choosing" to serve someone in the full knowledge that the slightest slip, the moment you displease them, you will be off for eternal torment.
The only way you can "choose" to serve someone, is if there is no downside to refusal. THAT is a choice. When the choice is "serve me every moment, or suffer forever", where is the choice?
The ONLY person it benefits is god, who can have his ego stroked by thinking "I MUST be great, they CHOSE me!"
....and try to forget the colossal stick he carries to help people "choose".