You take the good with the bad, there are many bad games out there too but that doesn't stop people from valuing and enjoying the good ones. There is enough good DLC on the market these days to warrant a different attitude towards it. Preorder DLC is where things get dicey more than anything else.
I think your motivations for saying anything about it are far less principled than you'd like us to believe anyway. Your views on these subjects aren't usually very rational and seemingly aren't even rooted in reality frequently either.