Why would they need to use IFR pickup Dick when they get a clearance. As seaid previously, on the incredibly rare circumstance that there is a delay in clearance, it is due to there being another IFR aircraft in CTA. And you want to just plough on through?
More often than not ATC will propose another option like a radial or heading to expect clearance on with a very minor delay.
Bear in mind that most aircraft that'll hit 8k fast enough to possibly cause a delay will be covered by company ops that require they don't do IFR pickup and furthermore, I know of places that will require the 'passive' party to IFR pickup to ask for avoidance.
How would you feel if you're IFR, punching along at 9k, or 13k and hear some jet denied a clearance due traffic in CTA only to have that jet then ask to punch through you on their own perogative?