Portal 2 are owned by valve, one of the largest gaming companies in the world. They deliver free content because their gross profit is in the millions, they are not an indie company. Minecraft has nearly 6 million sales and has a revenue of over $80,000,000. They made the decision to continue releasing content due to monetary gain (merchandise, lego, clothing, toys). They're now re-releasing their game on other consoles, making even more money. They have to become self-sustainable to continue releasing content. Show me a list of small indie companies who have released more than a couple of content updates for free. I agree that you should expect a few updates, but some (i'm not condoning everyone) of the Terraria community were just rude about it. There isn't a viable business structure for free content unless the original sales are excessive or it's supported by advertising.
Lol Terraria 2? Not every game has a sequel. This is a Starbound forum. Read this please http://community.playstarbound.com/index.php?threads/plans-for-post-release-content.10177/ It seems you're really upset about the updating situation of Terraria, but this is not the place to complain, nor do I think you sohlud be complaining in the first place. Please make sure you read that link, this will likely answer your question about Starbound.