What does it mean to "keep" the software? You can return the installation media, and say you erased the program, without having erased it. I would say that if you work for Microsoft and they give you a program free in order to test, then it's not a form of income. The program doesn't represent monetary value in that situation. Microsoft, the copyright holder, is licensing you to have a copy of that program under term…
This sounds surprisingly logical to me as a Swede. Here you can be taxed for income even if you didn’t receive anything at all. Take for instance a company office with a canteen exclusively for employees. Let’s say the canteen charges 20% under market price for a meal. In that case the employees can be taxed for having access to that canteen, even if they don’t eat there. This access is considered a taxable income.
I actually fail to see what is logical here. And I would go further by saying it is neither logical, nor fair.
First the basic point. Why should an employee be taxed for a service he is not making use of. That's a government trying to get more tax income than what they are entitled to, hidden under the guise of simplification. We are equal under the law, and therefore, theoretically, we are equal under taxes. It is irrelevant that someone has, or does not have access to such a canteen, if they are not making use of the facility, the net outcome is the same, and therefore, the taxation should be the same.
And then a point could be made about the relevancy of taxation in the canteen example. (Although it should not be forgotten that it was just a randomly quantified example for the sake of argument). But let's say that company A decides to provide a canteen, with food sold at cost price to its employees. This turns out to be 20% cheaper than eating in a random other canteen "at market price" (i.e. charging you for cost price + company B profit).
Now you are actually taxing the fact that company A decided to make the effort to setup a canteen, hire cooks/canteen employees, probably make a qualitative effort to offer better food, and not seek profit on the effort, when compared to company B, offering food at a higher price as it includes profit.
Congratulations, in a context of decreasing food quality offered by catering services world-wide, your taxation approach just further de-incentivized potential quality over taxation income. Further fully disregarding the fact that to offer a catering service, company A had to make investments, is employing personnel, buying food, etc, and is, therefore, already contributing more to global tax revenues for the state.
Furthermore, you are also unfairly putting non-profit catering services at a disadvantage, as, they too will be taxed more, as they are also offering their food below "market price". (Not too far-fetched, as such efforts are being set-up, with success, for school canteens, focusing on local, organic food, at operating cost-price)