First, a little background-information here: "quite to my surprise," I wound up creating a
(non-Linux ...) software product (a decade or so ago ...) that,
ahhh, "did quite well, thankye."
The licensing scheme that I used was "embarrassingly simple," in the sense that anyone who actually
was determined to break it, easily could have.
I also know, as a matter of record, that a certain number of people "out there" ...
did. However, those people never were ... my
customers. Therefore, I
ignored them.
Focus your attentions
exclusively(!) upon "completely satisfying": the people who understand the game of business, who wish to play it with you, and who in return expect
you to play it with them. Don't be distracted with worrying if they're stealing from you.
They are
not.
(They would be offended if you even suggested it.) Focus 100% of your attention on giving them "more than what they
paid for." (Spend
0% of your time wondering if they actually did, because
they didn't.) You'll find that your time will be 150%+ occupied in making sure that: "they are
so(!) completely satisfied that they will cheerfully recommend you, and your product, to all of their friends."
Yes, you must "put
some kind of padlock on the door," but its purpose will always be
(as one of my friends so aptly put it ...) "to keep the
honest people out." It's important only for the fact that it exists ... not that it can or cannot be defeated.
Game developers, in particular, should remember that there are hundreds of thousands or millions of games out there . . . and so, the odds of someone even knowing that your game
exists are very small. Since so many games are free, people are disinclined to pay
any amount of money for them. And, when they do, "99¢ is the going price," even though the soda you had for lunch costs more. You might be just as well off if they
did steal your game . . .