Quote: "So one day Steam will sell-out, closedown, or move on, and everyone will lose their rights to all their games, software, dlc etc. "
That's always been a concern to me as more and more things move into "the cloud", but I see Steam being around a long time. In the event they are bought, merged, whatever, any contracts that they have should still be honored by whoever is involved. Anyway, a piece of software bought today will be irrelevant in ten years anyway, unless it's continually updated (probably less). Besides that, TGC still holds the reigns here. If Steam disappeared tomorrow, I'm sure they would still honor anything that went through Steam. They're a good bunch! (Or they've been blowing smoke for the past decade and a half plus)
EDIT: Of course, I just purchased Mega Packs 1 and 2 on Steam and paid through PayPal. Upon completion, it forwarded me to my TGC account page, which had the key for one of them, but not the other. Upon refreshing the page to see if the other followed, the first one was gone. I will surely watch my bank account to make sure that transaction hasn't taken place!!
MAME Cab PC: i7 4770@3.4Ghz (passmark 9945), 12GB RAM, Win 8.1/64, GeForce GTX645 (passmark 1898); Shiny new laptop: i7 4800MQ@2.7Ghz (passmark 8586), 16GB RAM, Win 8.1/64, GeForce GTX870M (passmark 3598); Old laptop: i5@2.3Ghz, 8GB RAM, Win 7/64, Intel 3000 graphics