They have been mining with them like crazy and now it seems like it's more profitable to sell than continue to mine.
Most likely due to the upcoming hard form.
Yes, 3 companies getting out gear for the same algorithm at the same time is not a coincidence. They have been mining for the past N months and now they are dumping them for extra profit. Just because of that I will never, ever buy anything from them. One gets to wonder how many other coins are being ASIC mined and we don't know about it.
i bet my life eth / zcash are two of them
Would not surprise me in the least. But ethash has so huge network hasrate and the algo is specific, so all in all its not a big deal, unless there would be really huge number of ASICS working on it. Ethash profitability is still very good even with the low prices on the market. Unless you have really high electricity costs.