I call people dude a lot, which I don't really see as a problem, it's just a habit. However, my dad thinks it's funny to make fun of me every time I do so.

Dude, "dude" is a part of English now. Even MY dad says it sometimes.

In Brazil, people have the habit of calling each other "vei" which is a ridiculously shortened version of "velho" which means elderly

parents fail to understand

Wouldn't be funny if your dad started saying dude a lot.

dude is pretty much ingrained into my vocabulary.