Somehow extra hashes get MORE expensive per hash the more you buy? That's the opposite way round to how pricing usually works on bulk purchases.
The IPO share price point for reference is 0.0016 (represented by the public share payback clause). The 0.0014 and 0.0015 BTC tranches represent the early and immediate requirements for payments to Hashfast as well as setup costs. A discount was applied to the 1st two tranches to acknowledge the risk taken by those early (pre-tapeout news) investors.
Think you misunderstood my point here.
I wasn't talking about later shares being more expensive - I understand why you did that (though I don't necessarily agree with the reasoning).
I was talking about you getting less hash/USD from Hashfast.
You get more hashes (over 10% more) per BTC (and in absolute terms) according to the table for the next 7500 BTC you raise than for the final 7500 BTC after that.