On my United App, I see offerings of 80k miles (sometimes 90k miles) for opening a credit card, albeit one with a really high annual fee. Note I'm just a mere peon, without any status at any airline.

ETA, four offers total:

-20k for United Gateway Card (no annual fee),
-65k for United Explorer Card ($95 annual fee),
-70k and 500 PQP for United Quest Card ($250 annual fee),
-80k for United Club Infinite Card ($525 annual fee)