That particular passage was so influential that Jesus himself even referenced it in Matthew 12, and used it as an example to rebuke the Pharisees for their spirit of religious legalism. When they demanded to know why Jesus was healing people and allowing his disciples to pick heads of grain on the Sabbath, he simply said, "look, one of the great heroes of our faith lied and stole sacred bread in order to save his own skin."
The fact is, many heroes of our faith, from Abraham all the way to Peter, said and did things which were a bit immoral. Sometimes it was motivated by necessity, such as in David's case. Other times, as with Peter hacking off the ear of the High Priest's servant, it was motivated by a genuine desire to protect his Lord. Other times, however, as with Abraham, Isaac, and Jacob, the deceit which they habitually practiced was motivated more by some skewed sense of ambition (as in the case of Jacob impersonating Esau and stealing his blessing), or some perceived wrong (as in the case of Jacob defrauding Laban to increase his own sheep flocks), or maybe simply out of habit (Abraham repeatedly introduced Sarah as his sister, ostensibly because he feared for his safety, and Isaac later followed suit).
While it can be argued that everyone sins, and that's why we need grace, I think it's important to consider that these people all lived before the birth of Jesus, and long before the doctrine of "grace through faith" had ever been written down. Nevertheless, they were revered by scripture and called faithful men by God, so we can safely assume that their wanderings in the moral gray areas were either overlooked or else tacitly accepted. In particular with the case of Jacob, let's remember that God had in fact promised his mother Rebekah that the older of her sons would serve the younger, so it could hypothetically be argued that her duplicitous scheme to assist Jacob in supplanting Esau as the heir was part of God's plan.
I would never presume to say that any and all means are lawful for those of us who live under God's favor, in fact Romans 3:5-8 says quite the opposite. However, it is certainly worth noting that many so-called heroes of the faith were in fact prone to bouts of ruthless pragmatism. I think we sometimes get so caught up with our internal struggle to be a "good Christian" that we forget it's ok to be practical, and I daresay even a bit pragmatic in our approach to getting what we want.
Getting back to the passage cited at the top, I think it's funny how non-Christians will sometimes try to trap us with a test by saying, for example, "what if you and your family were starving, and you had no way to get food except to steal it. Would you violate your Biblical principles in order to save them?" To me, this is a false dilemma, because based on Jesus's example of commending David for his dishonest acquisition of sacred bread, the answer to the question "steal or starve?" is, quite simply, to steal.
If that reeks a bit too much of moral relativism, I understand your concern. I would simply point out that, according to the wisdom of Solomon, we shouldn't try to be overly wicked, but neither should we try to be overly-righteous. Since my recent epiphany regarding the impracticality of fatalistic beliefs, my propensity to trust "fate" to deliver me to my best possible future has been replaced with a more coldly logical assessment of how best to get from A to B ("A" being desire and "B" being result), which is by your own two feet. I assure you that I still believe God is in control, and whatever he opposes will simply not come to pass. That being said, you have no reason not to try your own hand at things when it is in your power to influence a given situation.
I'm sure some of you will find this message a bit too subversive, and that's ok. There are essentially two kinds of people in any given church body: those who believe in strict adherence to the letter of the law, and those who believe that as long as you trust Jesus, and do your best to do what you know is right, God will reward your faith. I clearly lean more toward the latter category.