It doesn't have to compete on just price. Trello is free (and I use it constantly), but using it still means having all of your data on remote servers. I can't use it at my job, for example, due to legitimate security concerns, but we could (in theory) use this new software instead.

I can't use Trello at work because some of the data that would be placed there may have a restrictive information classification.

I'd love to be able to buy a different tier of Trello service instead of stickers, but an open source clone will do too!

We've got an application that is very similar to trello (www.iferapp.com) that we are planning to offer in self hosted mode - we are going into beta very soon.

And here it is selfhosted.iferapp.com

There are reasons beyond money to use free (as in freedom) software.