So why offer a $100 coupon and not just make the price $100 less?
Psychological reasons? Where if you have the coupon you think its an opportunity?
I think it's pretty intelligent what Bitmain is doing.
1) The $100 coupons will drive up demand for the S7's they're trying to release. Demand is surely not what it once was with the halving coming up & increases in difficulty. I'm sure they have an efficient manufacturing process that's able to mass produce these machines. I think it's simply more profitable for them to drive up demand with incentives rather than to scale down their manufacturing process (especially in the long run). That's probably why the prices on the machines have been incrementally decreased with newer batches.
2) The coupons seem to be aimed directly at previous customers, it gives the illusion that Bitmain is giving back to their loyal customers and the mining community. From a PR stance, IF or when bitmain releases new products, previous customers who were satisfied will probably make a bulk of their orders.
3) Many people will purchase at MSRP and don't know about the coupons or wont bother trying to get them.
It would really suck if the next generation of miners are released a week or two after I place my order. It's not crazy to think they'll be released soon with diminishing demand/returns on their increasingly more primitive S7's.