They do provide flavor, but they are a very low water content pepper with thick skin and almost no flesh, so it is a more subtle flavor. If you take a dish and set aside a bit of the sauce, and put Thai Chilies in the rest and taste them side by side, you can notice a flavor difference in addition to the heat. It's more of a dry, smoky flavor as opposed to a sharp, pungent flavor, but it is still a flavoring agent. I prefer to use them powdered as opposed to whole/fresh, the flavor infusion is more pronounced that way, and provides a pretty damned good punch of heat per scoop!