Lens.com Lens Deceptive surcharge practices. 6% added to every order. Internet

Lens.com has a deceptive practice of adding 6% to every order without telling you why.  It is not listed on any line item, nor explained anywhere in the ordering process.

Go add anything to the cart, and do the calculations your self and you will find that it does not add up.

Ordering 4 boxes of contacts came to 39.99 x 4 = 159.96... but they wanted to charge me 170.36. 

After contacting them about it, it took 4 or 5 e-mails as I could not get anyone to explain it over the phone, they came up with some story about it but never anything that made any sence beyond a way to make their products look 6% cheaper than the competition while charging the same or more.

Very poor practice and they should remedy this immediately.