Well it's rare that you will find a cigarette that has been used for months or years and never cleaned. They are disposable. The previous user put their mouth on that cigarette maybe 10-20 times.

The 'vaper' could've used that thing ten thousand times since it's last cleaning - if they ever cleaned it.

Also after that whole Vitamin E scandal - we found out some vapes can kill you. You won't find random cigarettes that will do that unless you live in Breaking Bad.