That's why we went to abstinance. What is the difference how you prevent pregnancy if you don't want more children in the first place?! The whole basis of NFP is that you are open to children. Many people using it, I wager, are just using it as "legal" BC.
I know there are many who use NFP as just another form of BC. However, there are some legitimate reasons to abstain for a short time in order to postpone pregnancy. However, it is necessary to reevaluate each month to make sure it is still an issue.
I know there are other couples like you out there that abstain completely. I'm glad that it is a spiritual thing for you. I'm not sure I like the "animal urges" comment though. It's as if you saying that a natural, wonderful thing God gave married couples is somehow ugly. I hope that's not how you feel.