Really, why are you surprised?
A significant proportion of the people on this site (and others) have an agenda; typically, it is based around justifying their buying decisions or personal tastes to the detriment of others. Now, from this significant proportion there is a significant proportion that post any old nonsense to support their perspective, no matter the truth, no matter how much they know of the subject. Some of these poeple spout blatant lies and are often banned; others are more subtle.
Now, for any with experience, they know there are all sorts of people trolling topics with their bias, writing any old rubbish as long as it supports their platform (or platforms) of choice. For some, this is annoying, and they call such people out to point out why their opinions are not based on anything bar fanboy flag-waving.
So, when you make a blanket claim 'about the PS3 always requiring game installations' you must expect a reaction, primarily because your statement is wrong. In fact, it is so wrong that it makes it easy to believe that you don't have a PS3, especially as you sport a 360 gamertag in your signature with no PS3 equivalent. Now, for the people who have caught out liars before, such a false statement rings warning bells, and understandably so.
Really, the problem is less that people are calling you out, and more that you're making clearly false statements which, if based on experience, suggest you have a very limited game library. Nothing wrong with that, but you must understand why people are wary, surely?
Edit: Somewhat amusingly, the only PS3 game in your game collection -- Uncharted -- doesn't require an installation. Insert amusing comment of choice.
