Caesars fairly heavily promotes the "Diamond in a Day" concept, where you can become a Diamond cardholder (2nd highest tier) if you earn 5000 tier credits in day.

Most players at Caesars properties know the term "Diamond in a Day".

I suddenly started getting an influx of registrants where who are casino players.

I figured out why. If you google "Diamond in a Day", PFA is #1 result.

Blowin' up huge!

http://lmgtfy.com/?q=diamond+in+a+day