Sugar is just molecularly, very close to our bodies natural form of energy, Glucose. So it makes for a very fast absorption as the body does)n't take as long breaking it down and converting it over to glucose. When something converts easily to glucose.. the body just makes more insulin at one time rather than spreading it out as the body digests the food slowly.
Like a pixie stick will cause an insulin spike, because it's just sugar, and converts easily.
However, take the same grams of carbs from a potato as what's in a pixie stick.. and it takes much longer for the body to digest it, and convert the carbs from it into glucose, this causes the slow release of insulin.
If you time your insulin spikes properly there can be advantages to using sugar or foods high in sugar. Especially if you eat complex carbs most of the time. You'll be insulin sensitive, because your body doesn't deal with spikes constantly. A big spike will have a better effect every once in a while. Carb cycling further increases this sensitivity as you taper down your carbs and eventually rid yourself of nearly all insulin production.
Today, kids eat sugary cereals, drink pop, koolaid, fruit juices, eat enriched flours.. we get insulin overload from birth unless our parents are mindful and know their shit. I didn't figure it out until 14.. after realizing it, it almost disgusts me.
Anyways.. an alternative.. brown sugar? It will have no different effect. Just use it wisely. Be mindful of your simple sugar intake, time your spikes to receive the most benefit from them. Post workout is good.
This is just another reason why carb cycling is imperative. You're just pissing away something we're given naturally otherwise. If you don't care about the details.. don't have sugar in your diet. That's the easy way out though.