I think part of it's that, but it's also that people don't want to be told that what they're doing carries potential risks. I got into an argument just the other night with someone who was claiming his juice was positively, 100% diacetyl/diketone free. I argued that he couldn't possibly know that for sure unless he had his juice lab-tested. He kept saying, "the manufacturer assures me.. all over the website they say.. etc."
I wasn't telling him that his juice DEFINITELY had diacetyl in it, I was telling him that there's a possibility that comes with creamy/custardy juices for them to contain diketones, which could (potentially) be bad for you. I was met with such hostility that I came to the conclusion that even if I had factual evidence, written facts, he would still try and refute it. It's a very psychological thing. If you've been doing something one way for a while and someone tells you "that way is bad for you" you're gonna try and find reasons that it's not to justify it in your own head as being "safe".
ETA: Just realized your name is PERFECTLY appropriate for a discussion on the psychology behind denial.
^^ This is one reason why some regulation COULD be a good thing. It would be nice to know all of our juices are 100 percent what they say they are.
This "diketone situation" is exactly what has turned an occasional DIYer (mainly mixing pre-made juices) to the full-fledged variety. I've discovered that I really, really enjoy the bakery flavors -- and then I learned that diketones have the potential not just to irritate your lungs, but to DESTROY them.
If you buy pre-made juice, you have to take the word of whoever made that ejuice that there is nothing bad in it; given that pre-made ejuice runs about $.35-$1.00 per ml, yet costs only about a tenth (or less!) of that to actually *make*, the folks making ejuice have every reason to buy the cheapest ingredients they can find, to inflate their astonishing profit margin even further. The manufacturers of flavors, however, sell their flavors for quite inexpensive prices, and they must be high-quality, or people will simply buy from other manufacturers -- no recipe-making required, just to make a simple flavor, and several of the major flavor manufacturers have become aware of the vaping situation, and that some flavors commonly used for dietary purposes are distinctly unsafe for inhalation, and are either reformulating existing flavors, or creating new versions of old flavors with no diketones.
At some point, you have to trust someone when they say "no diketones" -- but I've decided that the flavor manufacturers are probably a safer bet than the ejuice makers with their appalling profit margins, since I do love those bakery flavors, and really would like to continue vaping them with some peace of mind that I'm not destroying my lungs. I quit smoking so I could STOP destroying my lungs, so if making my own ejuice is how I can better assure myself of safety, then that's what I'll do. Anyone who's as concerned about lung destruction as I am, check out bullcityvapor.com; they carry a TON of flavors from most if not all the major manufacturers, they show you very clearly which flavors are known to contain any diketones, and they have excellent prices and really fast shipping.
Andria
