Wow, I couldn't believe it. MS Store thuggery?

[CygnusOrion]

From reddit:

Bought a SP4 yesterday, sales associate threw in Microsoft Complete under my nose... (self.Surface)
submitted an hour ago by ZomgitsKevinZongSP4 i5, 8GB, 256
So I went to purchase a SP4 yesterday along with a type cover and Microsoft Office 2016. The sales associate asked me if I had a .edu email so I could use the student discount. I told him no since I don't have one. He then said that he'd give me the student discount anyways for the type cover.
Right before the sale he asked me about Microsoft Complete and I said I wasn't really interested. Anyways I went through with the transaction. Something seemed off though about the price. It wasn't until I returned home to discover the receipt both on paper and in my email had shown that I had actually bought Microsoft Complete but the sales associate had given me the student discount on the SP4 and the type cover, totaling just about $150 in savings.
Immediately I thought to get a refund for the unwarranted $150 charge but in retrospect it's actually kind of a nice deal considering I didn't have a .edu email. So how do I actually activate this thing? I know you have to register it with your device but all I have is a receipt saying that I bought it.
TL;DR "accidentally" bought Microsoft Complete, want to keep it, don't know how to register it to my SP4.

Can you imagine an Apple sales associate "accidentally" throwing in an AppleCare+ on someone? This is why people hate Microsoft.

 

[mark233]

I wonder if Microsoft instructs their sales associates to do that.