I love getting geeky about words so thank you for this comment! (I don’t teach English - I teach journalism and creative media.) I love that language is fluid and changes over time. “Sneaked,” as I would tell my students, is also correct yet it would trip most people up and slow down their reading since most people don’t use it that way now. I suppose because journalists (me) try to be colloquial I always go for how people speak. Thus, “snuck” has sneaked into English usage as well as my writing!