The emails were worded as if the codes are targeted, but I suspect that they could be used by anyone who is/becomes a member.
Emails were titled Extended: Member Exclusive- …….% off until 10 May only!
Details of 10% off:-
Book a participating hotel by 11:59PM on 10 May 2015 (US Central Time) via Hotelclub.com for stays before 31 December 2015 and instantly receive 10% off your hotel booking. Limit of one promotion code per booking. Promotion codes are non-transferable, not for resale and not redeemable for cash for any reason. Hotelclub reserves the right to change the terms and conditions of this promotion at any time without notification.
CODE: QUICK10
Details of 15% off:-
Book a participating hotel by 11:59PM on 10 May 2015 (US Central Time) via Hotelclub.com for stays before 31 December 2015 and instantly receive 15% off your hotel booking. Limit of one promotion code per booking. Promotion codes are non-transferable, not for resale and not redeemable for cash for any reason. Hotelclub reserves the right to change the terms and conditions of this promotion at any time without notification.
CODE: FAST15
- Offers are subject to availability and may change without notice prior to reservation confirmation. Specific offer terms and conditions are available on the website. Rates may not be available on some peak dates
Plus cashback and Amex and member rewards mentioned here
https://www.ozbargain.com.au/node/193077