Yes, reef keeping is an expensive hobby, and that's if you do everything right. If you don't then it's even more expensive.
Like the others said, I have also spent thousands on my reef systems over the years. However, it done because it's something you want to do, and get a lot of pleasure out of. Even people that have never even considered an aquarium before are impressed with reef systems. My younger nephew, when brought by his parents for a visit, was more interested in seeing the reef then he was visiting relatives.
For years, I have a large reef system, and a very small television. I was often asked why, and I could simply state that the shows were better on the reef.