Because alloy is a much better conductor for heat. And i wouldn't want a titanium light for a job, in which it is going to be hard used every day...It looks awesome, so it's good for shelf queens imho
By the way, i don't have a titanium light yet...
If you did have one, you'd realize that your Ti can take a beating, scratches, scuffs, etc., and you can then take a scotch brite pad to it and with some elbow grease, leave it as good as new. To shelf queen Ti is against the point, in my opinion. Some people have already scratched up their Ti Quarks so they already have the finish that all McGizmo's have when shipped (except Bead blasted, that is). But from what I've heard, it's easy to polish your lights up as well. Try that with chrome plated and you get horrible results. Anodizing comes off as well. Why Elzetta didn't just make a Ti light instead of Chrome plating, I'll never know, but that's a topic for another thread.
Ti is so hard that special tools are used to shape it. This makes not only the raw material expensive, but also the cost of working with it goes up. I'm not going to malign the fact that Ti doesn't transfer heat well because frankly, it's not big enough to make a difference in most lights. The Ti does just fine in that regard and I have two Ti lights that do things no other lights do (two beam profiles). Would I love those lights as much if they were made out of aluminum? Sure. But I'd lament the day I have to send it off to get re-anodized since I EDC one of these lights. Since they're both made out of Ti, I have NO suck worries and use them as hard as I want with the satisfaction that, barring electronics, the finish at least is something I can restore if necessary. How's that for a shelf queen?
The Al lights I have can get dinged up and I don't really care much. I think that part is mostly sour grapes, though, since if I could fix them up, I would. As it is, I take a permanent marker to it. But I know exactly where I've done it on each light. I love Ti, and not for shelf queens. I'd pay for all of my lights to be Ti just to be able to keep them forever, but frankly, there are some that I might be getting rid of on the marketplace soon, anyway . . . maybe not!