Perhaps so, but I have another theory: the box is priced to make the program work without creating a secondary market.
If the price were close to $40, folks who subscribe to cable or satellite (like me), and who don't need a box, would get a $40 coupon anyway just to get a box for free (plus local taxes). Then turn around and sell it on eBay for $20. Because the coupon program is tied to physical address, there are lots of potential buyers who need a third box at the same address (e.g. dorm rooms, rooming houses).
If the price were substantially above $60, it would discourage potential buyers who actually need boxes.
The $60 price point is high enough to prevent a secondary market but low enough to make the program workable.
Neal McLain