I guess you haven't done much cooking.

Put some nuts into a food processor and turn it on. What happens? First the nuts shatter into smaller fragements, then they get smaller again. Eventually they get really tiny and release oil and start to stick together, but before they get to that stage it forms a meal. If you go to most health food stores you'll find nut flours. If you spent any time in the cooking forums here you'd notice that people grind their own nuts into meal, or flour, all the time using simple coffee/spice grinders. They stop grinding before it gets too oily.

And you'll probably notice that most nut butters have oil added to them, because there just isn't enough oil in nuts alone to make a butter.

Seriously, take a macadamia nut. It's quite soft, it's also very high in fat. Smash it. Does it turn into nut butter?