[0x457]

They just don't burn hot enough to ignite. Remember - things burn at different temps.

[akira2501]

The vapor burns at a different temperature from the liquid. That's fun.

[0x457]

Yes, but it still requires higher temperature than cigarette can deliver.

[0x457]

Also should be clarified that only vapors of gasoline can be ignited - it can't mix with oxygen in non-gas form.