God, where's my Mercedes?

I watched New Life yesterday morning, and I heard something from Mrs. Chase I thought is true.

As we mature in our faith, we can't afford to be silly.

"God, I claim you are going to give me a mercedes."
Oh well, can you afford gas?
"No, but I want one anyway!"
Oh well, then, can you afford insurance?
"No, but I want one anyway!"
Do you know how to drive?
"No, but I still want one anyway!"

This is just a scenario but the message is clear. I myself is talking God into buying me the Mercedes I liked from the display (not literal though) when I know He loves us so much, he will not always do that.