The "GOD" Problem

I have noticed that some of the people I know have a "GOD" problem. They have a tendency to suggest that God would not want them to do anything that they wouldn't already want to do. One of my friends has an issue with giving. He doesn't think that God wants him to give any money to his church on a regular basis. So he doesn't give even though he is loaded with cash. He "gives" when he feels like it and leaves it at that. He is just one example of what I am talking about.
We all have a problem doing God's will every now and then. If we didn't then we wouldn't grow in the process. God chooses to stretch us like He stretched Moses, David, and even Paul. I believe God wants us to discard our preconceived notions in hope of glorifying Himself in our ignorance and inexperience.
Now let me just clarify that I am not illegitimizing true callings on peoples' lives. I am not saying that we all should be doing something because its just there to do. What I am talking about is a type of selfishness that inhibits God's work in our lives.
God wants to work in our lives. Not doing His will is a sin because it is disobedience. We should not allow ourselves to say no to God just because we don't like what He wants.