For what it's worth, yesterday an afternoon flight LAS-ORD left full on a 737-800. I'd imagine they'd need a little more fuel on a flight like that. There was also a LAS-IAD flight on a 320 that left with a few seats open and no nonrevs onboard, but I honestly don't know if that was a weight restriction issue or just no nonrevs even trying (it could happen)
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