I've seen it quite a bit in especially older e-commerce software, presumably developed for US use, then "internationalized" as a bit of an afterthought. I also

I've seen it quite a bit in especially older e-commerce software, presumably developed for US use, then "internationalized" as a bit of an afterthought. I also think that many non-native-english-speakers assume zip code is the appropriate translation of postal code since it features rather prominently in (exported) US pop culture. That doesn't make it correct, and I don't believe that some peoples unequivocally wrong usage of a term should oblige other people to qualify their correct and unambiguous usage of it.