I'm stunned at all these "rules" about Rhubarb. I've never grown it myself, but when I was a kid there was a nice large patch that was growing wild on the fence line of my neighbors house (perhaps *someone* planted it eon's ago but none of the neighbors could remember). We used to pick it as kids and snack on it (yes - raw!). We never had any idea the leaves were poisonous ... but we never ate them. In fact, we rarely finished an entire stalk when we snacked ... who could?? No-one harvested it to make anything ... we kids were the only ones picking it.
A lot my childhood "snacking" was in the "wild". Rhubarb, green apples (great when salted!), chew on burberis leaves, and of course vegetable garden raids
I used to carry a salt shaker because I never knew when a green apple or ripe red tomato would make itself available for snacking!