Don't worry, as long as you speak English I think you'll be forgiven
Now that I've said that people here don't like to address each other directly and therefore words like "babe", "chick" and so on are used, I must admit that there has been a debate much like this topic going on in Finland these past days.
In Finland it is normal to call strange men "uncles" and women "aunts". Not to their face (no one would try to catch your attention by calling "hi aunt!"), but when they are talking about someone to another person. For example in a bus a mother might tell her child to "go sit next to that aunt there". Also people of certain professions are often called aunts or uncles, for example kindergarten teachers, mailmen, lunchladies... Librarians are often called "library aunts".
What causes some debate is that many people feel old when they here someone talk about them this way. I admit it was a shock when I first heard myself being referred to as an aunt when I was only a teenager, maybe 14 years old

Now that I work in different libraries I hear myself being called an aunt almost every day and I have gotten used to it, so I don't take any offence. Really, those who refer to me as an "aunt" or a "library aunt" are mostly mothers and fathers who are talking to their children, so it's perfectly understandable. I mean, from a little child's point of view anyone over 12 years old is practically an adult, so it's natural for them to think of them as "aunts" and "uncles".