Not sure... I have not seen them advertised for a while. Personally I do not think that loyalty cards work. The only one that has ever work is the Tesco card and they needed their huge IT back up and marketing oomph to keep it going.
Here is one Salou loyalty card that is still active...
http://www.greenbananaguide.com/salou.html

AAAAAGH! DON'T mention that piece of garbage here!!
The best, and original, is the Salou Uncovered Gold card.

Hi Nick.... the Salou Gold Card seems to have gone. Their website address jumps to salouboxoffice.com
These immortal words spring to mind.......
This card is no more, It has ceased to be!, Its expired and gone to meet its maker, Its a stiff (or NOT), Bereft of life, RIP Goldcard, Its pushing up the daisies, Its metabolic processes are now history, Its kicked the bucket, Its shuffled off.... Salou Gold is an ex-loyalty card!
Unless someone else knows if it will be reborn at Easter?