The first time I saw VbV I checked the frame URI. When it came up as securesite.net I phoned up the merchant to tell them their site had been hacked. It’s unbelievable that they thought that was a good idea.
Having the word 'secure' as part of the domain name is the same type of nonsense as putting a GIF image of a padlock in the page content. Guarantees nothing and promotes ignorance about how things actually work.