These free skins can be taken at the distribution, and then just sell more expensive, pumping them. I did not do this, but a friend told me about this strategy, I started all over again myself and learned about it thanks to csgo trading sites, which had guides about selling and exchanging skins. At first, I just exchanged things, and then, when I began to play more, I thought that I could sell them, which I actually did. Sometimes I also just exchange it for other things, so that later I can sell it again, only more expensive, having got this or that thing that costs more.