Even as big as they are, I don't think they have that much power. So maybe they could do that with some items, but they're still going to have to package some items.
In some cases, it might even be less efficient to do it this way. It means spending more up front on packaging, so the time value of money is a factor. Also, some products never sell, so why create packaging for them that will never be used? And an already-packaged product may take up more space on warehouse shelves. It might only be 10% more space or something, but 10% of everything adds up.
Also, sometimes people order more than one item. It is probably more economical to ship everything in one box. (Postage would be lower, and it might still cost less even if Amazon does the delivery themselves.)
Even as big as they are, I don't think they have that much power. So maybe they could do that with some items, but they're still going to have to package some items.
In some cases, it might even be less efficient to do it this way. It means spending more up front on packaging, so the time value of money is a factor. Also, some products never sell, so why create packaging for them that will never be used? And an already-packaged product may take up more space on warehouse shelves. It might only be 10% more space or something, but 10% of everything adds up.
Also, sometimes people order more than one item. It is probably more economical to ship everything in one box. (Postage would be lower, and it might still cost less even if Amazon does the delivery themselves.)