When we get classless, moneyless, stateless society then sure, we won't need licenses at all. But as long as we have a world run by lecherous corporate MBA's, we need to use the current legal system to our advantage and keep our code safe from bad-faith actors who would steal from open source. The problem is not that corporations are greedy (they very well may be) but that the current relationship between the labor of writing code and the financial incentives of selling it is controlled by those bad-faith actors. They're going to do everything they possibly can to leech off of open source and give nothing back because because it makes financial sense for them to do so, and until you change the rules of that relationship, you honestly can't really blame them for it.