Diesel, I think that the issue at hand is that DL is approaching this from a rather broad standpoint, while we pax are approaching it from a more narrow one. DL's position is that once we purchase a specific itinerary, we have made a contractual obligation with the airline and must take the flights we have purchased. If we do not, then we should pay for the "privilege" of making changes.
Pax such as myself, however, approach things from this angle -- the ability to stand by on different flights (without added charges) is a distinct value-add, since it allows us to adjust our travel plans with one less stress inducer in the mix. If a meeting runs long or if a systems emergency pops up 15 minutes before I am to walk out the door, I have always known in the past that I stand a darn good chance of getting on another flight as soon as I get to the airport. If DL demands that I either pay for a more expensive ticket or pay a standby fee, then I shall have to pass the cost along to my clients, disappoint my clients by departing as scheduled (in effect passing along the inconvenience to my clients rather than accepting it myself), or I shall have to pay the higher cost and curtail my travel. None of these are particularly desirable to me, but one -- pay higher fares but fly less -- would probably run counter DL's aim. I suspect that the DL bean-counters expect to see the same load factors, plus an incremental increase in revenue from both standby fees and higher fare class purchases.
I'm sorry, folks, but I don't see that happening. If there's a way to keep the price down (so it doesn't get passed on to the client) and to reduce the inconvenience of standby travel (so that doesn't get passed on to the customer), then the pax are going to take the path of least resistance. And that appears to be defections -- where possible -- to other carriers like Southwest, JetBlue and AirTran.
Do some individuals abuse the system by buying cheap fares on inconvenient flights and then standing by on the flights they really wanted? I am sure they do. But consider this -- they filled a seat that would otherwise have departed empty. DL received revenue from them, and they got the seat they wanted. I myself sometimes connect at CVG in order to take advantage of slightly lower fares. But if it looks like foul weather's a-brewin' near CVG, I'll stand by on a nonstop. This helps me, DL, and other pax. It helps me because it gets me to my destination. It helps DL because there's one less misconnect to deal with and an extra open seat to sell (on the flight I would have connected to). And it helps other pax because there's one less PM clogging up the rerouting queues ahead of them.
Simply put, DL is asserting a privilege for itself that it does not concede to passengers. If rerouting, rescheduling and equipment changes can be done at DL's discretion (at times with little or no compensation to inconvenienced pax), then it seems that same-day standby can be permitted to pax with no charge.
If not, then perhaps it's time for reregulation of the airline industry.