I read it as you adding something to the discussion.
But I have noticed that certain subjects tend to rile people up - I think it's to do with categorizing people, almost like an -ism (as in racism or sexism). PC/mac is one of these; but there's also vi/emacs, Windows/Linux, programming languages, and even Holden/Ford (apparently). The so-called religious wars, that tend to bring out emotions. Probably because people identify with the product, and so any perceived slight is taken as a personal attack, therefore there's a wish to defend against it or to counter-attack, grabbing whatever means are available.
I've noticed that I've strayed into the area myself: without realizing it, I've used Mac/PC to make a point (about integrated hardware/software vs. modular components - the former is needed in the earlier years. It's an idea from Clayton Christianson, of the innovator's dilemma fame.) I wasn't attacked, but I got some odd responses... eventually I realized that it's just a touchy subject. Like sex, religion and politics.
I think you might have caused offense with the earlier part of your comment, where you seem to be implying that Mac purchasers lack "the wherewithal to tell the difference." I can see that causing offense, even though you are a Mac user yourself, and you intended it in a neutral way. And that's coming from me, who's not a Mac user.
I agree that the denotation of the statement is neutral - the same statement is true of evaluating professional work in general: dentists, surgeons, barristers, plumbers, car repairers, etc... and of course coding (for the non-coder.) How do you know if you are being ripped off? You don't.
But your point is well taken. Most people react first with their stomachs, genitals, and fists before their brains. I'm starting to hate them. I suspect they are subject to the same foibles as the ones who treat Asians like cartoons and doormats.
There's also: http://news.ycombinator.com/item?id=589200
I only mention these two links because I've started trying to apply them to myself, and they seem to be helping. When people react badly, I first think "it's not me", "this is a one-off" and "it's only in this specific circumstance". That helps me to be "liberal in how I listen" by defusing my anger/judgmentalism. Then I try to be "strict in how I speak" by being factual (this is hard, but I can do it) and warmly/kindly (I'm not so good at this part - but that's how I'd like them and me to be.)
BTW: I think you make your point about consumers very clear in the above - it wasn't as clear before. hmmmm... maybe explicitly mentioning "in general" (as you do here) is a shortcut to avoiding people taking things personally, if one senses they might. I recall in Ben Franklin's autobiography, he reinvented his whole style of expression to be less confrontation, to "it may be so", "it appears to be" and such like, as he was getting in too many duels (a.k.a. flame wars?)