I don't do sugar, since giving my kids a big bag of sugar is not conducive to them sitting quietly in their seats. I have read that a lollipop on the descent will help with ear pain (as will breastfeeding).
I bought my kids tiny wheely backpacks of their own and put lots of snacks and new toys in them. They get to pull them thru the airport like grownups, but can't open them until we get in our seats.
Protein snacks like granola bars, trail mix, sesame sticks, snapea crisps, dried mangoes, etc. Cheese and pringles. (babybel or string cheese are individually wrapped) Treats they don't always get, but aren't total sugar either.
New toys/activities from the dollar store - buy lots and get 2 so they don't fight over them. Cheap toys means you don't care if they get lost or broken. Silly putty. Funny glasses. Markers, crayons, stickers, paper.
Cool new sippy cup. (buy juice and water after security)