The typical .edu discount from Apple on largish purchases is about $100, regardless of whether that's a $600 final tag or a $2000 final tag. So, somewhere between 14% and 5%.
If Apple sells 50% of Macs to the .edu discount market, that's a difference to you of somewhere between 2.5% and 7%.
Or, you can accept that Apple's prices are not set by the market so much as by their marketing department.