单选题 .    We've found that eating habits vary (变化) so much that it does not make sense to include meals in the price of our tours. We want to give you the freedom of choosing restaurants and ordering food that suits your taste and budget (预算).
    As our hotels offer anything from coffee and toast to a full American breakfast at every reasonable prices, it will never be a problem for you to start the day in the way you to like best. At lunch stops, your tour guide will show you where you can find salads, soups, and sandwiches.
    Dinner time is your chance to try some local food. Sometimes the tour guide will let you to have dinner at a restaurant of your own choice. At other times he or she will recommend a restaurant at your hotel. Years of research have taught us which restaurants reliably serve a good choice of delightful dishes at down-to-earth prices.
    In Mexico, Alaska, and the Yukon, where your restaurant choice may be limited, we include some meals. The meals provided are clearly stated on the tour pages.1.   According to the passage, most meals are not included in the price of tours mainly because ______.