Do you use coupons? Doesn't it feel great to pay less at the checkout? So what happens to that money do you save? Do you really know? Do you end up spending it on other stuff because deep down you really know you have a little bit of extra spending cash?
What I do is after I get home from the store I literally add up my savings, record it in a spreadsheet and then go online a pay down my debt or I put it aside in a money market fund. Why? So I put my savings or extra cash to work.
I also get a sense that I am "buying" something and getting something twice. First, I saved some money at checkout (good feeling) and then I paid down a credit card or even invested it. Each time I recorded it so I can see my progress.
If you shop at Target you can also get a 5% discount using their Red Card. Everytime I shop I save between $20 and $30 with my coupons and Red Card combined. It may only be $30 at a pop, but it still feels great!
So go ahead, pay yourself twice!