Can somebody explain why people think BVB sound like A7x?

Now, I know Avenged Sevenfold aren't the best band out there, but now even Metal Hammer has used them as an example to describe Black Veil Brides. Can anyone explain to me exactly why music critics feel that these bands have ever sounded similar, of all the crap that gets released? I used to be a huge A7x fan and I'm seriously not feeling it... And no, I'm not saying this because it even irritates me - say what you like about either band; I'm just curious from a critical perspective.