Buying is better over the long haul
It really does depend on how you can use your timeshare programs. I believe over time you can actually come out ahead with owning over time, but it depends on how well you know how to use your system and if you use your timeshare a great deal. I own with DRI and Marriott. With DRI's points, I can come out ahead of a renter. For example, I have 30000 points. I can use points for the most expensive timeshares in their system for a 1 bdrm and would be 7500 points. This is the equivalent of $780. I looked at redweek a few minutes ago to compare those cheaper rates and I saw studios at $695 on Honolulu. There were a couple in excess of $1400 there. I did notice that prices really dropped when there was less than a month or so left to rent the villas. However, as mentioned before, your airfare could be very expensive. Right at this very minute there is a one bedroom at DRI Kanapaali Beach Club in Maui for 5750 points which is under $600 with an ocean view. That compares with the last minute deals people can get renting and it's actually better.
My maintenance fees are almost 3300 with Club fees. At peak season, I could stay 4 weeks. When I retire I don't plan to be in Hawaii during peak season and I can be there for nearly 8 weeks. In fact, if I waited for 60 days for flex, I could be there for nearly four months. That would be a really good deal. Traveling to Europe is same except that if one is using their points in places like England you come out even better as you are now using those points against the British pound and in France against the euro. In these cases timeshares come out ahead when you know that the dollar is weaker against those two currencies.
Marriott doesn't offer the same flexibility, but if I offer Ko Olina during the busiest time of summer, I can get more than maitenance fees for my 2 bdrm. I pay $1500 and can easily get even in this economy. However, I do like staying there myself so I don't give it up.
The problem I notice with many people with timeshares is that they do not use them or they don't know how to maximize the benefits they have with them. They really can be a better buy. My wife has a friend visiting California for the first time. She is traveling with her son and his friend. The boys are 13 and 14 years old. They are staying at a nice Sheraton in Universal City. However, they are in one room with two twin beds and a rollaway paying a great rate of over $200 a night. There is no kitchen, no separate bedroom and no washer and dryer. We live in southern California where there are many properties throughout. Thus, I can do several flex change reservations and come out way ahead of the renters. Palm Springs, San Luis Obispo and the Bay area are all within a 6 hours of my house. I come out ahead.