When you start with the correct mindset "Giorgio Armani, Tom ford, Gucci, Prada clothes are all basically for guys who have a lot of disposable income and who want to be able to buy something quickly which fits fairly well and is of decent quality with a high end design of the moment"
Ignoring your rather distasteful need to make presumptions about the income of others in your attempt to prove a point, there is a reason some expensive brands receive more vitriol than others. Your arguments about appealing to the wealthy and the value of convenience could just as easily be made for Ralph Lauren Black Label, Ralph Lauren Purple Label and many other higher quality brands that are readily accessible in retail environments. Armani charges a massive brand premium and doesn't give you anything for it. To your car example, imagine if an entry level Audi sold for 2/3 of the price of a Ferrari. A Ferrari may be "just a car," but it is a pretty damn awesome one and I can understand why someone would want to buy one. I would have a major issue with the entry level Audi selling for 2/3 of the price of a Ferrari regardless of whether I could afford it. Same thing with Armani vs. other brands that offer the same convenience. I definitely understand the reason for the high end RTW business; I just happen to view Armani is a prestigious way of buying fake product for far too close to the price of the real thing. Slight exaggeration mind you.