Because he's being very simple-minded IMO. I thought we all heard about Foxconn and the fact that the conditions are actually better than other companies. If you call that virtual slave labor conditions, then how can you in good conscience purchase from the competitors who abuse workers even more? It hasn't been mentioned in his post, but if you really believe in what you say, you should avoid every company who abuses its workers, not just Apple's (It doesn't mean the pressure shouldn't be hardest on Apple, I'm just saying that you should acknowledge that everyone is abusing poor workers, and blame all of them accordingly).
And in general, his tone is incredibly immature, like a 13 year old who's shouting in schoolyard. He twists facts (points 2 and 4), exaggerates (points 1, 3 and 6), and seems to care about things that actually don't matter at all (points 7 and 8). And I don't get his #5 issue at all.
So, I feel sad for him both because I think he's very immature, and that he can't articulate what he wants to say very well. He won't be a successful blogger if he continues this way, and would actually hurt his cause, with which I agree a little (just like that asshole Mike Daisy did).