Vulcan, I agree with your sentiments but not with your place of blame: compensation for airline employees is low and travel benefits is a perk that keeps most employees happy and on a level playing field with other comperable occupations.
How Platinums end up in coach is more of an issue for revenue control than for non-rev employees.
When ever I took a first-class seat as a non-rev, I never thought to myself "ha-ha, I'm showing those high-revenue earning passengers stuck in coach a lesson or two..." Instead, I thought, "phew, thank God there's an empty seat somewhere on this plane, and what a treat it is to sit in 1st class --it pays for all the stress/hard work gained with minimal pay the airline employee needs to deal with..."
Domestically, unless an agent is breaking a rule (and rules are broken by many people across every industry), a paying passenger always takes priority over a non-rev leisure traveler. (Although I must say that if anyone were to benefit from the no-standby-for-free rule going into effect, it'd be the non-revs.) Internationally, within the 72 hour window, seats filled with non-rev's are a perk deserved by the employees or are best left empty to preserve the value of the seat. (As much as I enjoy using Platinum status to sit up-front and get bummed whenever I see an empty seat when I'm in the back, I equally love it when the cabin has empty seats and the service is more personalized/dedicated to my needs.)
Still, the fault of the process is with revenue control and the wizards at OnePass who do not give away more available seats to award redeemers. If an award was available at the same frequency seats available for sale are, the playing field would be much more level for all those vying for a seat up-front ...whether it be for revenue (cash or miles) or non-rev (employee leisure travel) passengers.
I cannot fault a flight attendant or a ramp agent or some other employee for the misdeeds of an executive in Houston or wherever the airline HQ may be who wants to wring every ounce of cash out of a flight -even at the expense of the most loyal, most frequent revenue-generating passengers.