A few questions to ask before you deliberately light an open flame on your guitar in a crowded club to a drunk crowd post-Great White.
How large are the stages you play? 1000 sq feet with no chance of having anyone or anything coming close to you while the headstock blazes gloriously and garners much deserved attention? Pretty much every gig I've ever played I've had to be VERY careful because if I swung the headstock of my bass around I might take out a cymbal or two or a guitarist or vocalist (or hapless friend on stage or audience member up close). And that was without a 2000 degree headstock. Maybe the stages you play are like Wembley Stadium, so if that's not a problem, let's ask some more questions.
Any curtains around, above, in front of the stage, or off to the sides? Are they all fire retardant (think Great White), or are all of your gigs played in extremely well lit areas devoid of any sort of hanging fabric? Most stages I play on have black curtains either on the side of the stage or the front, or above (heat rises), and to be honest, I've never thought to ask the club owners, "Are these curtains fire retardant? I want to set my instrument ablaze at the last moment of the set." Let's say that there are no curtains, and if there are curtains, they won't catch fire because either the stages you play are SO big you won't go near them with what is essentially a lit torch or they are all flame retardant and won't ignite. Next question.
Anything else remotely flammable nearby? Open booze? Does everyone in your band wear fire-retardant clothes? Anyone in the band with hairspray or flammable stuff (mousse, gel, sterno) in their hair to keep the mohawk cresting proudly, or is everyone bald, dressed head to toe in aluminum foil and armed with fire extinguishers? Let say that setting another bandmate (or stage hand or fan) on fire isn't going to possibly happen, and ask another question.
At the end of your song (when you presumably want to light the torch), is everyone in the band going crazy, jumping around with you, or do they stand far away and moderate their activity? Let's assume that the stage IS 1000 sq ft and that no one will be coming within 20 feet of you and can't possibly get burned because either they are stationary at the climax to your song or keeping far away. Next.
Is it LEGAL for you to intentionally light an open fire in a crowded club? Yeah, I know it's not cool to think of such things and kinda lame-o, but while the idea of getting arrested at a show (like Jim Morrison) sounds cool, it really sucks. Fines and crap. Let's assume that there are no laws or legal restrictions against lighting open fires in crowded clubs. There are still other questions.
Are all the club owners in your area cool with open fire on the stage? Are they all pyromaniacs with no insurance riders? That might be. It's possible that club owners don't really care if there are open flames in their crowded bars (maybe they like being interviewed the next morning after the "incident" as they are leaving the police station). Would you be willing to ask their permission to burn your guitar and risk their livelihoods and insurance coverage to get attention? If you don't want to ask them for fear of being having the gig canceled and being called an idiot (or worse), then, don't do it. That's simple.
How will the drunk, screaming, emotionally hyped up, traditionally not-so-well-behaved PUNK crowd react? Will they like the sight of insta-light bass guitar TOO much and take things into their own hands? After all, many will have lighters and alcohol. IF even ONE drunk, drugged up high and unstable person (what are the odds of someone like that at the gig) does - YOU are equally responsible for ANYTHING that results, and the police will want to invite you down for a chat and a phone call. Let's assume that there will be no drunk, aggressive, high, unstable people at your gig who loves it too much.
What about the opposite? What if there is someone who is in a booze fueled drug addled state (can't be!), sees the golden torchlight, and FREAKS out not realizing that it was intentional stunt designed to evoke, I don't know, admiration or something, and make a rush for the door, inspiring other people in the dark (except for the flame) club to follow suit? Hey - we thought of a new name "PANIC! AT THE DISCO!" OK - maybe not, maybe the well-behaved and sober crowd will realize what's happening, and not take the blazing prop for more than it is. Maybe.
Maybe EVERYTHING will go off perfectly. Maybe you will light the bass on fire. Maybe it won't light at all? How high will it go? How will you put it out? How will you test it? How will you handle a problem if something unforeseen happens? Where's the fire extinguisher? How's your insurance? Do you have a lawyer on speed dial? Maybe it will be the greatest show on earth, and maybe you will successfully avoid any flammable curtains, people, substances, laws, club owners, drunk patrons, etc., etc., etc.
Maybe. But maybe not - and for what? What could POSSIBLY go wrong, with SO much at stake. A lit headstock. Whoop. If I saw that from the audience, I would think, "What an idiot" and then "Jimi did it better."