As with Smackababy (who tows the same line in nearly every thread where someone raises a concern they have) just because it doesn't affect/matter to you, doesn't invalidate the concern. Added cost is added cost, regardless if you have it or not. What you state above can be said about anything and still is meaningless for that same reason. Telling someone they should "have this already because it's cheap" is what is not valid.
Aside from the comment that it could possibly hurt sales for direct downloaders, I don't see a post anywhere that someone states they aren't getting the game due to the size, simply a conversation about why it is so big and what is the need for it (and even, is there a way to remove some of that size). They are all valid questions and one of the pros of having PC versions.
I'm well aware that an issue can affect others and not myself. I just don't buy it for HDD's. I gave my reasons, and I believe them to hold up. My argument wasn't simply "it's cheap now," as you over-simplified it. My argument was that it's been cheap for years now. Long enough that only people that can't run the game would have it as a legitimate complaint. And cheap enough that a married college student on a tight budget was still able to stick a 1 TB HDD in my computer.
The flip side to your argument is that just because a person has a concern does not validate it. They may see it as one in their mind, but at the end of day, it's frivolous. We all do it with different things. I believe that any complaints in regards to HDD space are frivolous or a result of short-sightedness. Or do you really go into a conspiracy board where they're trying to link Illuminati to everything and tell them their concerns should be addressed? I see this as no different.
I would also argue that adding a HDD cost and directly associating it with a single game is a fallacy. You'll obviously use that drive for other things. One game or program or whatever may have been an impetus, but to just say that Titanfall cost $60 + $100 is false. Unless you only bought that HDD for Titanfall and it's the only thing that will ever be on it. Upgrades are upgrades. The timing is up to the buyer, but it's stupid to say Windows 8 cost a person $800+ if they decided to put it on a new computer.
Post #575 is what I was referencing, and you are correct that it wasn't deterring the actual poster, but I wasn't saying it was either.
I've seen people complain about the 6v6 and the refresh rate. Both of those seemed valid to me, as the arguments put up were compelling. Neither bother or affect me, but I accepted those concerns. I've seen people say that the gameplay didn't grab them at all. I didn't try to convince them they were wrong.
I just don't accept the storage space concern as valid. It's not like I'm acting entitled that what I think is what everyone thinks. I'm saying that I don't buy the HDD requirement as a valid complaint for anyone, especially people on a board like this one.
It's interesting that you would even argue from the "just because you don't care doesn't mean others don't" angle given your signature.