if you think the company offering incentives to workover is leverage for  

Think of it this way then.

You have negotiated a $ per year (either salary or hourly), to work a certain amount of time in that year. You also recieve/negotiated benefits with your employer. Such as a 401K match, sick time, vacation time, medical insurance, dental, life insurance, you get the point.

The benefits portion of your pay averages 35%-45% of your compensation, depending on what you select. When you work overtime, do you acrue extra vacation time, better insurance coverage, a higher 401K employer match? I would be willing to bet, you do not. In the HAA world anyway. So, your 1.5 workover/overtime pay, is not really overtime pay at all.... It is you normal wage, or very close to it, when you include the average benefit package offered. 

Chew on that a bit