I have some insulated strap on cup holders that I use on our double jogger. I have some on the handles for those not in the stroller and then I have two on the sides of the stroller for passenger use. I don't use anything for snacks. At home, if they need snacks, I stick it in a cup and let them figure it out.
ETA: They are called Strollr Holldr II and I purchased them at Babies R Us for ~$4.99