Why would they do that? Are there that many windows computers with thunderbolt?
They put Thunderbolt on their interfaces because itís where their customers, the mid to higher end of the Mac-based market, are. If they have the hardware on their interfaces, they figured they might as well appeal to a larger audience by making it work in Windows as well. They also know that Intel is building Thunderbolt 3 into its newer chipsets and will eventually become more common in the Windows world.