Why not? By virtue of my profession, I spend many hours in front of a computer during the day. Every time I receive a text -- which is pretty often, I'm wishing I could read respond on the device I'm currently using, instead of switching screens/keyboards.
What would make someone prefer using the other device?
One of the main reasons I stick with Google Voice for my primary number is so I can send and receive SMS messages from a computer with a keyboard. There's a Windows 8 app so I can use it on my desktop and Surface natively, and it works well enough on my iPhone too, so it's everywhere for me.
I wouldn't even consider replacing that with WhatsApp, specifically because they don't have/allow clients on desktop/laptop devices. As in, I thought about checking WhatsApp out, searched for info on desktop clients, a Trillian plugin, or something, and immediately ruled out using it at all based on the lack of those things.
Don't know why this is being downvoted, because it's probably true. Maybe not for the crowed of HN, but outside of that a lot of people use phones/tablets a lot more than laptops - especially younger people.
