Favre moved on to Minn because the Jets didn't want him anymore. He didn't play well the one season he was in NY he tossed the same number of picks as TD's. Plus he was being indecisive about his future and that put the Jets off. He asked for his release knowing they weren't all that committed to him and they did it willingly. As for Manning he was released because he was injured and there was a risk so Indy let him go knowing they had Andrew Luck waiting for them with the #1 overall pick.
As for Culter he was traded because he and Josh McDaniel's had a falling out. They couldn't repair their relationship and Cutler wanted out. Denver didn't have much choice so they traded him. It resulted in wasting a #1 on Tebow and having to go after Peyton Manning.
There's plenty of logic behind my position and I've detailed it. There's certainly no logic behind your position because it leaves the Cowboys with a scrub at QB. Jerry already has issues with the offense he's not about to leave his team in the hands of Kyle Orton and make matters worse.
At 34 he won't get a guaranteed long-term deal from anyone. Any contract he's offered is going to leave the team an option. The Cowboys would pay him very well for 3 years with an option. If you think anyone is going to guarantee him big money until he's pushing 40 you're kidding yourself.
You honestly believe the Chiefs think a QB like Romo who chokes repeatedly in elimination games is a guy that can win them a championship?

It's not like they don't know his history. The only reason he would be traded is because the Cowboys don't think he's capable of winning a championship.
I can't recall any situation where a starting QB who was playing at a "high level" was traded strictly because their team couldn't afford to pay them. Every starting QB I can think of who was either allowed to walk or was traded was due to age/declining skills, injury or a team conflict where they refused to play for the organization.
It would be the best thing for the Cowboys because they can't be competitive without a QB who possesses Romo's skill set. They need a playmaker at the position who's mobile and can make plays outside the pocket. By resigning Romo it keeps the team competitive and gives them some time to find his replacement. Without Romo the Cowboys are a 4-5 win team. You put an average QB behind the Cowboys OL and give them no running game and no opportunistic defense that creates turnovers and this team will go from mediocre to bad.
No plan is guaranteed but my plan keeps Romo in Dallas at least 3 years allowing us to be competitive and giving us time to find and develop his replacement.