These type of comments are really interesting. My experience is it's not quite like this.
Let's say you are in a position where you have enough disposable income so that for you personally, time is more important than the money needed to buy a high end audio system. Let's say that you like audio but don't have the time or knowledge to put lots of pieces together and test components in isolation. It's also impossible to tell from reviews because they are all over the place. Let's say you can hire someone who designs complete audio systems, the kind of person who will go to your house/apartment, do an acoustical test and configure everything. You give them a budget of $100-$150k to get a system for you. Person has been recommended to you from a friend.
You go to his/her studio and listen to various speakers and set ups. Different speakers do sound different. There's no pressure, actually, you can come back and listen several times on different days to be sure.
You are not being an idiot. You don't have time to really care about each individual component, and you know you are probably buying unnecessary things. That's understood. You also know that some of the cost is made up because the consultant gets discounts and you don't pay list price on anything (easy to check). It happens to be the M Scaler is part of the set up, but is about 3-5% of the total cost of the set up. You don't have time or really care about each individual component. Since you know you like how it sounds as a whole you go for it. System set-up and you are happy.
Is it a waste of money? Sure, on some level. If I did it again I would leave out the M Scaler as part of the package. But it's not irrational. Just depends on your personal valuing of time vs. money. It's a lot of work to test audio components, assuming you have the know-how. One of the reasons the M Scaler stayed in my system despite my doubts is it didn't seem to hurt, and I'd rather listen to my system than swap cables which are admittedly in an inconvenient spot for me (out of sight).
I only found this website this year. And as I get into the technical aspects audio more and more, I am curious about what each of these parts do, if anything. And I've frankly been a little shocked at the lack of transparency of the industry, and in particular the audio reviewing industry. I have to think that if a company provides you with a review model, it will bias you a bit because you want the next one, right? You need products to review, or your website will never take off. So if you have a positive evaluation of a company loaned product you will post it, but if you have a negative evaluation, you have every incentive to simply not post the review rather than give a negative review. Hence my support of what Amir is trying to do.