At that cheap price, you get their basic cable with Dynamic Filtering which does make a nice difference as many many people have reported here and elsewhere.
Since when is $150 cheap for a power cord? Just because it is at the bottom of their line, does not mean it should be made this poorly.
The size and stiffness of the cord is a marketing technique, so that their customers assume it sounds better, because it is large and heavy. This technique is working well for them, just as Bose and Monster's marketing strategies are successful.