Truly, from a business and not emotional perspective it's like marketing 101 backwards. Instead of finding new distribution outlets for a product, they are imploding them inward and cutting out distribution channels. Now if they were marketing some really exclusive product for like rich people who like things exclusive, then the club only distribution angle would work. However, Dark Shadows has never been the rich person's market who need exclusive feel goods to buy the DVD products.
After a wider distribution, it strikes me as rather odd that the narrow distribution channel is being taken.
Some of us may very well have to join the little exclusive club to get the beginning of the series on DVD but many of us won't be able to afford to do so as has already been discussed. There are two choices: take a risk with this proposal that those whom are loyal DVD buying customers would stop buying this product or widen the distribution a wee bit and generate another revenue building channel or two. I would think a wider distribution release would produce more revenue and not alienate the fan base.
If I was selling a product and not a service, I would never engage in such a folly as narrowing my distribution channel ever. It would be product suicide.