From out of nowhere, something that I hadn't even noticed jumped out at me. Camp Kidney? Bean scouts? Kidney beans! — Farmelle
Slinkman even says in "Edward's Big Bag", "Kidney Beans, front and centre!"
Not only that, but the Jelly Trio's name. Now, bear in mind that jelly beans are very different from the average bean, which just goes to show that Lazlo, Clam and Raj aren't like other Bean Scouts.
In Boxing Edward, After finding out Dave sends letters to his grandma, (and needing the stamps anyway to mail himself out of camp), Edward tricks him into giving him all his stamps by going into this sob story about how Dave's grandma's eyesight is probably not what it used to be and she probably won't be able to read his letters anyway. Dave then declares he'll never send letters to his grandma again. That's gonna have some dire consequences.
Unless if Ping-Pong or any other family members tell him that her eyesight is fine anyway.