Old-school, wooden popsicle sticks in South Brooklyn?
There is a difference between basic craft sticks and food grade sticks for use in making popsicles. Amazon does indeed have food grade sticks (along with a big selection of molds in a wide price range) in fairly large quantities, but sadly the shipping is more than the item.
Perhaps check at the Cook's Companion on Atlantic; since there's been an uptick in interest in homemade popsicle making this season, they probably carry molds and may carry the sticks or be able to source them for you.
If Winn's Discount is still on Court at Degraw, which I believe it is, check in there. When I lived in CG, Winn's stocked just about everything under the sun.
A Cook's Companion
197 Atlantic Ave, Brooklyn, NY 11201
re: jen kalb
You could try this place on Livingston http://www.barclayschoolsupplies.com/ although I'm not sure if they're "food quality". (It's a nice store, I just don't know if there's a difference, although it being a school supply store I'd imagine it's expected that everything will end up in a kid's mouth.)