This is a difficult situation because you never want to offend a customer, however it sounds like these customers are not your ideal type of customer because they sound young. I am assuming by the name that you run a bike store, if so, most of your customers are not repeat customers so you cant lose that much by telling a white lie. I would say that you recently had a customer come in that complained that there was not a lot of help in the store when if fact there was it was just that they were talking to you (the kids that were hanging out) as a result my boss has asked us to focus on our customers and would be upset if it happens again