A lot of folks have asked me "why on earth would you pay for this if it's free online?" and there are plenty of nice little reasons to, like the cloud saves and the steam achievements, and the music. But personally for me it's more of a little thank you note to the developers. It's a small token of my appreciation for the unceasing effort given to this cute little passion project over the course of the past eight years. Five bucks is a steal, honestly.