Let's see...you find an offer that is really too good to be true. You know that this kind of deal has come and quickly gone in the past. It is extensively discussed in a public forum. You do get some benefit from it. The offer quickly evaporates. And you are SURPRISED/OFFENDED?????
OK, the tone of the letter sucks. But honestly, would any of us done business with Chase if this offer did not exist? We all took advantage of a loophole and did violate the spirit of the offer (and it really is their fault that they did not place proper restrictions on the offer), so what is everyone up in arms about? Enjoy the miles you got, and enjoy spending the TCs, and get on with life...this plane has left the gate...