Thought Of The Day: Smackdown And The Main Event

I know the brand split is basically dead, but this is ridiculous.The last time Smackdown had a main event of a PPV (excluding the Rumble which isn’t a Smackdown match) was Hell in a Cell 2010.  I know Smackdown is the lower level show, but wouldn’t it help a bit to have them close out a show once in awhile?  You’ve already sold the show, so does it really matter if the Smackdown match goes on last?  Especially if you have a somewhat weak Raw main event?

Is there a reason for this that I’m not getting?