Originally Posted by
flyerCO
This 95% of time means they have bunch of cargo and don't have weight or space available for carryons to go below.
Considering the weather was abysmal all over the Eastern US yesterday, it's far more likely the issue was additional fuel for deviations, holding and alternate requirements.
I flew DTW-RDU yesterday on a full A320 and we were also at our weight limit. That's only a 500mi flight. We had to wait at the gate a few extra minutes for dispatch to re-work our numbers (likely they just increase the taxi fuel burn because we were so close to limit).
Weight restrictions happen for lots of reasons (weather, tankering, MEL, IROPS), but cargo is rarely one of them. If it's going to be close, it's simply not loaded until they know they have enough capacity.