Restocking fee on a maintenance paln

I recently purchased an Alienware laptop for $1800 but the total cost with taxes and the 4 year premium support came to $2928.  I'm now being told that I purchased the laptop as a business and I'm going to be charged a 15% restocking fee on the total = $440.  How can they legally charge a restocking fee on a maintenance plan?  I even offered to pay the 15% on the cost of the laptop alone but they wouldn't do it.  I had already ordered a faster Alienware before any of this came to light.  I'm now going to end up with two Alienwares.  Is this really happening??