Bose has a market for their products, the spent the time and money on marketing and designated store fronts, and believe it or not there is not much that will compete with it...
Think about it, not everyone {actually very few} people want speakers bigger than the size of my fist, they want a few almost invisible speakers that just plug and play, name another system that does that? I don't know if you ever set up a bose system, but it can't get much easier, the cables are color coded and you just run them and done, plus they will come out and hook it up for free... Plus they do crazy financing, I have a cousin that bought a bose system when he built his house, they came out and installed it and he financed it through them for 0% interest!!! Plus when he wanted to upgraded they buoght his old system back {gave him more than he could have ever sold it for} and installed the new one, and financed that one, when it breaks they come out and fix it too...
So add all that stuff up and they leave a lot of the stuff we own in the dust, the only place we win is sq and output.. So if you want small, convenient, easy, no interest, no work, ect get Bose, if you want to have bigger more conspicuous speakers, do the work to figure out the gear, set it up yourself, ect. then go for doing it yourself, the problem is a lot of people don't want to or know how or want to learn how to buy and setup there own gear.. We are a small portion of the market believe it or not, the bulk of people don't even care about surround sound or sq, then there are the htib guys {bose falls into this category}, then the hardcore guys, with a little grey between each category of course...