Originally Posted by
Moebius01
Because many business travelers are limited to coach seat purchase prices, thus rely on upgrades as their only chance of flying in the comfort of F. Since this is making it easy (and tempting) for more leisure travelers to buy up to F, the business travelers wouldn't like it.
If they were doing it at the gate after upgrades process, that's one thing. Doing it at ticketing. Sucks for us.
DL is doing it increasingly at the gate, after upgrades even for AS and AF-KL elites have already been done.