If you’ve spent any time hitting up the giant wholesalers or other markets this holiday season, you’ve probably figured out that you can make a full meal out of the tasty little samples they often dish out. Which seems like a good thing, for you…and for your wallet. But a new study shows that these tempting little treats really do entice you to buy what you try…and maybe some other stuff like it.

Researchers tracked the sales in half a dozen stores that provided samples of snacks in four categories: healthy, salty, frozen, or branded by a large coffee-shop chain. They found that noshing while shopping convinces consumers to buy the featured product more often than does simply seeing the product displayed at the end of the aisle.

They also found that repeating the sample offering multiple times translates into sustained interest in the product…and that stores that have a smaller assortment of products for sale benefit more than the warehouse-sized emporia. The finding is served up in the Journal of Retailing.

The researchers also discovered that the effect extends beyond the product itself…such that, for example, nibbling on one brand of cookies makes you hungry for cookies in general—including those from competing brands.

Which suggests that a rising tide really does lift all boats. Or at least that a tray of free taquitos will certainly lift a lot of shoppers’ spirits…and will keep those registers ringing well into the new year.