I actually think it would taste pretty good. They had pickle pringles for a short time here in the US and they were surprisingly really good.
Just to go on a tangent tonight: Pringles alone has several unusual flavors only sold in Japan. In addition to favorites like "salt" and "nacho cheese", they have local flavors like "wasabi nori", "yakkitori", and "karaage" Pringles. Even stranger things like "chicken nuggets and sauce" a la the McDonalds meal, "mushroom soup", "Brazillian grilled steak" as a special item, "roast chicken", and "baked potato" are sold as flavors of Pringles.
So again, sauerkraut is definitely an option. They mean it when they say Japanese entrepenuers are masters of selling you stuff you didn't know you needed but absolutely do need.