It's a joke but I only knew that because Snap is/was (as of S1) hosted on GCP and not AWS. Crackle happens to be the name of a video on demand company.
It's a reference to the breakfast cereal of the same name.
Pedantic clarification for the unfamiliar: the breakfast cereal is named Rice Krispies while Snap, Crackle, and Pop are the names of the cartoon mascots on the box.
It's a reference to the breakfast cereal of the same name.