yes, he helped build such a big lead, it didn't make any sense to leave him out there and expose him to injury
it was awesome
yes, it is great to beat the crap out of another team well enough that key starters can be rested and protected. And while it would be awesome for Zeke to keep the stats piling up for all of us to take vicarious pride in, it has always been considered "how it's done" at the NFL level to take out your stars in blowout garbage time.
Also, this was a test for Dallas. They did not come out flat against a bad opponent, nor did they look past them. The Cowboys beat some ass which is what should have happened when the two teams are compared. This could have easily been a harder game just based upon taking Cleveland too lightly. This team did not take Cleveland lightly at all in my opinion.