Yes, the Wii hardware was sold at a profit. The PS3, though, was definitely at a loss. People took it apart, and the total cost of parts at the best prices available in available in large volume was well over the retail price (not all of which goes to Sony).
Interesting, particularly as it suggests the XBox 360 has been sold at a profit for at least four years now. So, of the three major home systems (as distinct from portables), at least two are being sold at a profit, further reducing the argument in favour of restricting their use due to recovering initial costs.
What makes most sense probably is for them to restrict use initially when (1) there is a shortage of hardware and (2) the hardware is often being sold at a loss per unit.
When the hardware is not being sold at a loss (which was from day one for Wii, and after years for the others) and the units are readily available so that repurposing isn't preventing gamers from getting them, then dropping all restrictions makes sense. They'll sell more units (which is good for them since the units are profitable per unit) and hence make more money.
edit: details: http://arstechnica.com/gaming/news/2006/11/8239.ars