Actually, lot's of people get a HELOC for emergency purposes.See, when you're currently well employed, well financially, tt's easy to get a loan, including a HELOC. But suppose you have a bad string of luck, out of a job, get into a big health issue and for some reason insurance isn't up to snuff. You're short on cash, you won't be able take a loan out at that point. Some people get HELOC's when they can, "just" in case. Trying to refinance equity out of a home when your unemployed and need money is not too easy.
It' very similar to dating or employment. When you have a significant other or have a job, it's much easier to find something else. When you really need a significant other or a job when you lose your previous one, it's just that much more difficult….
So several people i know have HELOCs with 0 balance. It's just added "just in case". I've been too lazy to get one myself, but one of these days I will. Ok, the real reason is that I froze my credit files, and forgot where I put the unfreeze pins to allow someone to pull a credit report. Oopps.