We knew this day would come. Amari Cooper is entering the final season of his rookie deal which is when players begin talking extension. The Raiders valued a first round pick more than what they were getting from Coop, so when the Cowboys offered it, they took it.
The Cowboys knew this was coming as well and made the deal figuring having a Pro Bowl receiver was more valuable than what turned out to be a low first round pick. Even if that Pro Bowl receiver would be looking to get paid very soon.