hillsongs music is a bit different from the preaching...while other churches sing and play their songs. i dont think they copy their sermons or preaching. eg there is no official Hillsong bible or prayer book.
Hillsong churches probably have their own spin on the gospel, just as other denoms churches do. I havent been to one or listened online so cant really judge, though I have read and know of several believers who have left those churches for various reasons and very often it has to do with financial problems.
its enough to know that something is not right though this wont be every believers experience of course.
I also believe if you do have lots of personal funds in general you dont flash it around and spend big on your for yourself if you want to stay humble. Most people will put the money toward helping others, not themselves.
My brother is an engineer and he designs yachts and some of the yachts are for very wealthy people who have MILLIONS to spend. They are just toys to them and often after a few years when they are sick of it they will sell it to buy an even bigger one. Its not like its their home its just an extra toy. Cos on other hand I know christians who sold their own home to live on a yacht cos they love sailing and they want to go round the world to spread the gospel.