When we were there last week, it was anything $4 and under. This included Goofy's candy company. My kids got the rice krispy treats custom ordered with all the fixings and it counted as their snack. They thought that was the best thing going.
We did the pretzels before we had the DDP but the girl told us anything that was $4 or less was covered by the snack credit. She said there were a few exceptions but I didn't ask what they were.
And the "buy four pieces of fudge, get two pieces free" isn't included. Individual fudge is - but you can't use snack credits for any or all of the four pieces and then still get the two free. Did that make sense?