I don't normally need the triple's granny gear (47/36/24 x 11-30, 8 speed) on my Holdsworth, but it's there for extreme angles of ascent (eg: up to King's YH in the BCM) and fatigue at silly o'clock, somewhere slightly lumpy. The weight penalty of a 24t ring and a bit extra on the crank must be minimal. And the front shifts are much less extreme than a wide range double, plus it all works perfectly with down tube levers - I don't think indexed STI triple levers were ever very slick or reliable. My experience of indexed doubles isn't all that great - my 53/39 on the road bike needs a bit of willpower and force to get a good up-shift, likewise son's 50/34.
Matches the un-cool saddlebag, mudguards, sandals etc. There's nothing so uncool as caring if you're cool, to misquote Andy Warhol.