In Russia, it's expected that powerful people are wealthy. The whole point of becoming a powerful person is to get rich and powerful. The grassroots anti-government sentiment does exist but it's not about the fact that the people in power are rich. It's about the fact that the country is run badly and as a result poor people are poor or getting poorer, if you get what I mean.
A lot of people have watched the video about the palace. Just like a lot of poor people read tabloid stories about how rich celebs live in their mansions or watch it on TV. Because this is what a success story looks like in Russia. Most people won't bat an eyelid on the palace, stables and weird machines if they are satisfied with their own lives.