That says it all right there. It's just not worth the risk to save a few bucks. For the cost of 30 bucks (2 gallons of fuel) you might save someone's life. And, you might not even realize it. You might keep your radio from bleeding into frequencies that are not RC--in other words, your plane might fly great, and you might not shoot anyone down, but are you sure you're not interfering with a construction crew down the road, or something else where someone else could potentially get hurt? You're risking everything you own, and putting your family in financial jeopardy if your insurance drops a claim.

BTW,
Ignorance is NO excuse of the law. That, by the way, is law. So it doesn't matter if you know or not. These are not wal-mart toys we're dealing with here.