Doom Fogger - useless for roaches

Doom fogger is useless for ****roaches. 5 tins later and my restaurant is still infested. No difference at all. Why, because they live in nooks and crannies that the fogger doesn't get to. It shows ****roaches on the tin, but doesn't specify that the roaches must be willing to expose themselves to a Doom shower, which of course they wont. This product is generally a waste of money...