Yes, "the" is not needed here and it makes the sentence sound awkward.

Below cost is a retail term usually associated with online vendors. Since these companies have lower overhead (expenditures, etc.) and private equity funding, they can often sell products at "below cost". Meaning that in the short term they aren't making any profits, as their sale price is lower than the cost to make the actual product 

In this case, Williams is acting as a third-party vendor which is benefiting from "below cost products".

Hope that helps :)