No, I did not compare this item with the other colt items on the site. You searched Colt, I searched Mk 18 and the item (that has now been renamed) popped up. It was until after this all went down I went back and looked at the other products.
No I do not expect free upgrades.
As I was pondering whether or not to purchase the item, I read/watched every review I could find, compared prices with other websites. It quickly became clear that there were 2 VFC Mark 18 variants - one with colt trades, and one with VFC trades. The only MK 18 with VFC trades I could find for sale ANYWHERE on the internet, does not have the tan low profile front sight, as well as a different rear sight. It is also not called "Colt MK 18 Mod 1" because it has no COLT markings.
The one I got is apparently a 3rd variant, one with correct sites but also did not have any COLT markings (same for those you pointed out) so the COLT description is misleading.
I'm not trying to argue whether or not I should have asked, because clearly I should have and this is my fault, I'm just trying to point out that I think it would be a reasonably easy mistake to make given the description and thus some consideration in coughing up a fair chunk of change for a restock fee.