Because they seemed like a good deal when they first came around, and they were, so they boomed in popularity. Then everyone started offering them, the prices got jacked up and now you'll struggle to find an alternative.
Also, the very very short answer: More money
Cars have (or had, I don't know if they're still included) an electric lighter that you pushed in to heat up. It was basically a little metal ring that got really hot. So I think it probably is the heat.
I remember my friend also had a plasma lighter, that unsurprisingly used plasma to light things. It made a really scary noise in the wind and hurt like a motherfucker to touch. We were 18 and dumb.