It's a tricky line. I cook a lot and I don't have a sweet tooth in general (though I have some particular favorite sweets, of course). I've come to realize that I'm actually deficient in knowing when I should use sugar as an ingredient; because I only think of it as a sweetener (and have little desire to sweeten the food I cook), I've become ignorant of when you need to use it (for texture, to offset an undesirable sour or bitter flavor, or for other chemical properties).