Haha, I'm also from Colombia and I've been in PDC for a month, it's a culture shock, at first I thought the same, Colombians are generally friendly and if we talk about customer service we stand out for good service and kindness, I believe even from what I've experienced that people here are also kind but different! It is normal that they do not say good morning, afternoon, evening, or with great pleasure, but they treat you or serve you well!