That's the point that many are largely making. The Cowboys misuse FA often. They nickle and dime in FA when there are options to improve the roster and then go through a season where clear holes that most fans saw, and they didn't, rear their heads. A prime example was WR two years ago. They nickle and dimed FA, probably using the same logic you do, and by the 8th game they had to panic and trade a #1 pick for a WR. They have a clear hole at RDE and good, fairly cheap and short term options available and they are sitting it out, at least for now.