Rear bumper with a tow rating?

I'm looking at CBI stuff but I noticed the rear bumper says "not load rated".
My questions are: what does that even mean? There's a ton of steel there, how can it not be tow rated?

Also, if it is really not rated to tow with, is there any other rear bumper that IS tow rated?
I want to tow and I have a winch tray that hooks up to a 2 inch receiver hitch. I can easily see having to do some winching from the back, or pulling a friend out by hooking up a recovery strap to your rear hitch.

Or is this an "insurance" thing where manufactures will not say their product is tow rated because that means something if everything goes wrong because you installed it wrong?

 

A frame mounted hitch is more durable and offers more allowable tow weight.

 

It's an insurance thing, to get tested and rated would cost more money than it's worth to these small businesses making armor.

ARB has a rear bumper that uses the OEM tow assembly but you don't get the clearance gains of most aftermarket bumpers

 

It's the last part. I don't think CBI or any other company would be willing to pay the price for the Feds to sign off on their product being able to tow "X" lbs. Auto manufacturers go through extensive testing on their vehicles to get a certified tow rating. No fab shop is going to do that.

ARBs front bumpers are "air bag compatible" and I can only imagine what getting that ensued, but they are probably the biggest aftermarket bumper supplier in the world