Locks are there to keep honest people honest.

To expand on the saying, they're not there to be insurmountable. Just to be hard enough to make it easier to do things the right way.

And often they’re there so no one can plausibly say they didn’t know what they were doing or stumbled into it accidentally. You can’t “accidentally” go through a door with a padlock on it.

I’d guess it’s something similar with this dongle. You can’t “accidentally” run the software without the dongle.