I am not surpised at all Wolf Knight. I have bought a number of cabinets from IKEA for the storage rooms we have and they were all made 100% correctly by carpenter with supervision and inspection and have been loaded extensively . No problems or whatsover .. yet .. ( 2 years now) 
Probably it is the weight issue? IKEA is quite popular in HK for twenty years. They used to be of very high quality, living up to our expectation on European products. I have been using their stuffs for many years, bookcase, beds and desks. Even in the days in US, I also bought my computer desk and necessities from the only IKEA miles away. And I notice their quality be on the wane since last year, when my home went through thorough renovation and the BILLY case was bought. Would it be cost saving strategy in the Asia market? I actually googled a bit and some people in the West also faced the same problem...bending layering. I guess they are not supposed to hold books, despite being called bookcase
The only two non-bending layers are those without books but PLAYMOBIL ONLY
It is installed by the IKEA staffs too
