According to this report in USA Today, Blu-ray sales are growing while DVD sales are dropping: http://www.usatoday.com/tech/news/story/2012-01-10/blu-ray-sales-2011/52473310/1.
I think that the demand (or lack thereof) that you experience for Blu-ray disk depends on several things: (1)_ Whether your clients are watching 1080p HD on a large screen or not; (2) The speed of the broadband connection that your clients have with clients having high-speed connections more likely to stream than those with low speed connections; (3) The availability of 1080p content by sttreaming. Here in the U.S. there are very few sources for streaming 1080p content and they demand very fast connections.
In my mind, there is no question that the image quality of Blu-ray media is clearly superior to that provided by streaming. However, I watch most video on a 100 in. wide screen using a Sony VPL-VW90ES projector.
Finally, I would add that Apple has made the creation of Blu-ray content difficult on Mac computers by failing to support Blu-ray even in the OS. Yes, there are third party vendors (Adobe, Roxio, etc.), but Blu-ray is still very much an "add on" to a Mac computer whereas on Windows Blu-ray is quite often included in a good desktop computer. Thus, if you ask a PC user vs. a Mac user a question about demand for Blu-ray, you are quite likely to get very different answers.
Tom