"Hai" is a word with no meaning sometimes. Actually I think that means " I'm listening." , if I had to choose . If you don't say anything, the other person might say "Are you listening?"
こんにちはたかさん、in US and Canada, all the Starbucks ask the customer’s names and after a few minutes, the drinks and snacks are delivered to them, how about in Japan? Do you also need to wait they calling your name?
I don't even understand the very first greeting! "Hai! Ou ka ga i shimasu". How on earth does this mean "Can I help you?" I understand the use of "hai", but the rest of the sentence just doesn't make sense!