USA gov blockins urls but not homepage ?

[relaxme]

So, I went to my vendor of mag, and I can saw the item on the list, but when I click there it sent me to a 404 not found. I talked with the seller, and seller told me that the exactly url was working on their site. So, basically I was available to see   www.example.com but not www.example.com/buy-mag

So I tried with a none USA proxy, and guess what ? www.example.com/buy-mag was there !  So I tried with different proxies from different USA states, and in some where working and on others was a 404 not found results! 
Anybody have any news on this ? anybody found the same problem ?
Thanks , I can`t believe this is actually happen. It is kinda silly they are actually doing this.