The new mantra in the consumer marketplace these days is simple: If you reward them, they will come. According to a survey of 1,161 Americans conducted by New York City-based retail consultancy WSL Strategic Retail, 82 percent of consumers participate in at least one retail loyalty program. Spendthrift youngsters and mature consumers are more likely to sign up for such a program; 85 percent of shoppers ages 18 to 35, and 83 percent of those 55 and older, reap the benefits of membership, versus 78 percent of consumers ages 35 to 54. Interestingly, participation in loyalty programs seems to increase with household income. The participation rate in low-income households (less than $50,000 annually) is 76 percent, compared with 84 percent of those earning $50,000 to $100,000 and 93 percent of those earning $100,000 a year or more. Apparently, membership does have its privileges.