There are some people on absurd crusades of one sort or another for this debate. In my experience the more adamant a person is about this choice the more they are just looking for validation of their own perspective. Lots of insecure people just want to feel that they are more right than someone else. It's why so many of these discussions devolve into name calling, the statements "it's a fact" and "lack of intelligence" get tossed about wildly by individuals struggling for some sort of approval from the world. Comedy option to the first anonymous internet personality that brings up the term Nazi is the true winner of a debate with no consequence or persuasive weight. There are some outright trolling fan-boys still out there too, that only serve to fan flames.
In general the internet has brought out much more (in volume) of the worst of humanity, than the good discussion and debates we could be having. I wouldn't let the general tenor of these exchanges get you down. The hate and rants and vitriol with persuasive us-versus-them mentality isn't really gamers talking; it's just insecurities amplified by online anonymity.
I would like to think that console players know they are using computers to play those games. Consoles are computers, our phones are computers of sorts, tablets etc. Neither camp is stupid about what the devices do in general. They all "get it" to some degree.
The PC camp with an SLI, Tri or quad-graphics set up are often justifying the money they spent so they can feel superior. Due to this feeling those people might think they ARE getting a better gaming experience. But you are right in that they may not be getting the same level of enjoyment out of a game as a 9-year-old playing Minecraft on an iPad. I see that as a separate issue from the debate though.
Some of this debate has to revolve around price. Consoles are generally less money. If price is a factor, consoles will be a way games can be experienced in a more effective 'bang for your buck' equation.
Some of the debate has to be around usefulness of the tool in general. Arguably a PC can do more than a console, just not the exact same things. Where do phones fit into gamer culture? Tablets? Or how about Facebook games?
Some of it has to do with the familiarity and even a bit of brand loyalty. It's easy for someone to route for Sony or Microsoft, two companies, not much to keep track of, the systems will only have 2 or 3 revisions over their life spans and it's just "easier". If friends have one system, and you want to play WITH them, then the choice is pretty much made for you. With computers there are just SO MANY variables. Lots of people don't want to know, and don't want to think about these things.
Consoles are pretty much guaranteed to play every title released for that platform. If you buy a PS1 title today, a system from 1995, it will still work on that system. Computer titles aren't that simple. OS consideration, hard drive space, drivers, graphics card, sound, compatibility settings; you get where I'm going ... it's not AS easy and things don't always "just work" on a PC.
As for the Benchmark comparison mentality.
MPC has to rely on benchmarks to differentiate hardware reviews in an objective way. Computer engineers and builders (many of those types on this site) also use the same statistics to compare these features. Hardware junkies, overclockers and system tweakers, not exactly all of them are gamers like you are using the term. I think that gamers really don't care much about this kind of number system if they can play the games they want, at settings they can enjoy the title by on any device they enjoy using.
Grand Theft Auto 5 got a lot of attention because of the sales numbers. Gaming is a huge industry that has yet to reach saturation. Valve is developing the Steam Machine concept, there are Android-based game systems now that plug into TVs. iPads all over my office have some games on them. Something as 'simple' as Candy Crush can make millions in a month.
Gamers will be excited about anything that furthers the industry. But not everyone takes the time to appreciate the way all these systems serve different entertainment niches.