OJ and the Glory of God

Monday night, I read the chapter five in Pierced by the Word, called "How to Drink Orange Juice to the Glory of God".
In a paragraph John Piper says:
"So I draw this somber conclusion: It is sin to eat or drink or do anything not for the glory of God. In other words, sin is not just a list of harmful things (killing, stealing, etc.). Sin is leaving God out of account in the ordinary affairs of your life. Sin is anything you do that you don't do for the glory of God.
But what do unbelievers do for the glory of God? Nothing. Therefore everything they do is sinful. That is what I mean by saying that, apart from saving grace, all we do is morally ruined.
This, of course, raises the practical question: Well, how do we "eat and drink" to the glory of God? Say, orange juice for breakfast?
One answer is found in 1 Timothy 4:3-5:
[Some] forbid marriage and require abstinence from foods that God created to be received with thanksgiving by those who believe and know the truth. For everything created by God is good, and nothing is to be rejected if it is received with thanksgiving, for it is made holy by the word of God and prayer.
Orange juice was "created to be received with thanksgiving by those who believe... the truth." Therefore, unbelievers cannont use orange juice for the purpose God intended-- namely, as an occasion for heartfelt thanksgiving to God from a true hear of faith."
Later he says;
"Believing this truth in the Word and offering thanks in prayer is one way we drink orange juice to the glory of God."
I must confess, most of the time I don't pray before a meal, or really offer up any kinda thanksgiving to our Father. This was very convicting. How often do I stop and pray? Not much...