If that were true, you would see 90% of Mac users running Windows. Since that's not the case, and many Mac users bought their Macs in order not to run Windows, I'd say their OS has some weight in this.
I think you could equally argue that the hardware is given away to ensure that the software works in a consistent way - they are a full service company, they do both hardware and software, they offer [consumer] products that are ready to use.
