That brings up an interesting question (at least to me). Do the airlines report loads of only paying passengers or do they include non-revs? I would think or hope that it's only paying passengers.

DEN-IND-DEN on Frontier is a drag. There are always employees (non-revs) flying back and forth as we still have some parts of the operation in IND.

I'm not sure how often the jumpseat fills up, but there are a number of projects in IND that pilots participate in (with the IBT's permission).