Sorry, but the Featured Product grid is not designed to do something like that, it is designed to display additional images for a product.
If you want to do something like the example I think you would need to set up sale by units, by box, and by bulk as child products of each main product in Virtuemart. Then on the category browse page set it up to display child products with an add to cart button for each.
I think this is possible with Virtuemart, but it would probably require some programming, also you would need to be quite familiar with the way Virtuemart works. You might try looking at other e-commerce extensions, eg RedShop or HikaShop to see if they will do this sort of thing for you.
