Going to play devil's advocate on this post... sorry bu!
Credit has be marketed to us with such ferocity and guise that the banks and creditors literally have people banging down their doors, begging "Please sell me your product." (honestly, how many businesses out there literally have millions of people begging for your products as if it were life or death) It just does not make sense to spend more money to bow at the feet of the the great FICO only to have to continue to "borrow" money to pay it back for more than you borrowed (interest)... only to have a score that allows you to borrow more money and pay more interest...
What if instead of spending say... $5000 on your credit card to get your "free" air miles, you just paid $500 for a plane ticket... you would have already made an instant saving of potentially $4500 (or atleast never spent).
I've subscribed to a debt-free living. Wife and I are working our way out of debt and will never ever take out another loan again (with exception perhaps a mortgage... but even then, we'll pay it off in 6 years). Credit cards and debt is stupid... and I can admit to stupid.
