There was an article the other day here in multiple German newspapers that IKEA will start selling through shops like Amazon and Alibaba besides their own ecommerce presence. If I remember correctly they mentioned that IKEA has twice the margin compared to all other competitors. They also mentioned that the biggest problem in the delivery process seems to be damage to these bulky items.
Every time I've ordered from IKEA the items have been damaged. Fortunately it has been minimal and they are so cheap it doesn't really matter.
This is an example of where you want an item to be shipped a single time. Amazon has a problem where big items can end up looking like they've been shipped two or three times, which of course increases the chances of damage.
[1]http://www.handelsblatt.com/unternehmen/handel-konsumgueter/... (can't find the exact print-article I read...)
edit: grammar