How customers are greeted sets the tone of any establishment. In the hospitality industry, getting too comfortable and casual with guests, too quickly, has the potential to leave a bad impression. Always remember that each guest interaction has the chance to represent or misrepresent your business or brand.
When you’re thoughtful about the way you greet your customers, that yields better results than any splashy new logo or 20% off coupon ever could. Make them feel important and respected. The relationship may morph itself into a more relaxed and casual one, but the error is taking it there before the customer tells you it is okay. And remember, in many cases, your customer may never want to be your "buddy," "guy," or "gal."