Some people like a Timex because it accurately and reliably tells the time. Some people like a Timex because it shows they are pragmatic and sensible in how they spend their money. Some people like a Rolex because it has a nice weight and feel on their arm and will look like new 10 years later. Some people like a Rolex because it shows they have discerning tastes and the money to support those tastes. How does that compare to amps? Well, some people like their MP3 player because it can hold thousands of songs and play them forever anywhere and everywhere. Some people like their lower cost amp because it shows that they are pragmatic and want reliability. Some people like very expensive amps because it shows that they have discerning tastes and the money to support those tastes. Some people like their expensive amps because the sound is what they have been searching for since forever. And owning it means giving up something else.
You know what is a real waste? Someone who drives a Porsche just to commute to work. This is a car meant to be driven, driven by a driver with the skill to appreciate it. Comparably, a hifi system purchased by someone who does not really listen and appreciate the music it can make. To say all amps sound the same is simply someone who has not yet listened, or heard the music different amps and systems can make.