My sister-in-law's boyfriend didn't "ask" for her hand, he did tell her parents (my in-laws) before hand though. He basically said "I love your daughter very much and I'm going to ask her to marry me". That way they knew first, but he wasn't saying "can I marry your daughter".

Justin didn't ask my parents first. Mostly because my mom never payed any attention to me anyway and my dad is a very difficult man.