When someone is ordering their household items online, they will have to factor in shipping costs and sometimes, the cost of putting the item together. The same is true with cabinets for the home. RTA cabinets are going to be shipped much easier because they are ready to be assembled.
All of the pieces will lay flat and be able to be placed in a box for easy shipping to a home or a business. There are many different sizes that will be shipped like this also. Every cabinet is going to have a different design too. This needs to be matched to the décor of the home that is already there.