It would have been crazy to buy the launch price of $79. Even the subscription price makes no sense since you can BUY very good remote desktop apps for 10-$20 with no subscription.
You can buy all sorts of remote desktop terminals on Mac/iOS/Windows for anywhere from .99$ to 99.99$
However none of them include a hosted service as I presume this does (as does logmein, etc).
The hosted service gives the ability for the solution to "just work" in contrast to other solutions which require port forwarding / firewall rules / ddns setup. While those might not be a problem for some people to organize, they are a significant problem to those people who either don't have the technical wherewithal or, more crucially, don't or can't have access to make the changes they would need to make a static setup work.
The problem with a hosted service is that there is ongoing costs associated with it's use and operation that need to be recouped. People by and large have shown a preference for monthly financing, hence the prevalence of that model, however most companies have a way of buying yearly, or even bi-yearly via invoice, allowing you to treat it more like a traditional software purchase.
Karl P