If you think what I have said is me suggesting that someone does go and fill their car AC system with a nice flammable mix then great - you've taken something said out of context and twisted it to get all dramatic about it. You could also pipe antifreeze into the AC system if you tried hard enough.
The point was both of those mentioned materials (which are also referred to as refrigerants when used as such!) are easily obtainable because they are not fluorinated gases and thus anyone could, if so inclined whilst it is not advisable for safety reasons, put them into their AC system.
And that is, I'm betting, what is in a lot of the other DIY top up kits. If they say they only contain 'hydrocarbon' or 'natural' gases with no mention of HFCs... then what else is it going to be? Legitimate question - there may be something I don't know about.
For all the snowflakes out there that don't understand common sense here is the disclaimer just for you - I don't endorse putting anything other than the manufacturer's specified refrigerant and oil into your car's air conditioning system.