^ I think it really depends on the person and the family and what they can afford. Western brides on a budget wouldn't do much of this stuff either, so money is a big factor. If they can afford it then I think a lot of brides here are opting for this.. and then why wouldn't you get someone to do it for you? It's just too much hassle to do it yourself. I don't think anyone would have the view of "'wots the point spending soo much on flowers might as well do it urself at home'?" unless money was an issue.
There is another point too, for example my dad has always made it clear that he wouldn't spend huge amounts of money on lavish weddings for us because he firmly believes that wedding's should be simple and you should instead give a large gift to charity. A lot of people have this Islamic point of view, so yea, they would probably do flowers and decorations themselves instead of spend more money. This is something that makes muslim people consider carefully what they are spending money on that other people don't really consider.
agree, again it depends on each family.