Thank you for that clarification. I remember all the banter back and forth during its announcement on the official forums and speculations of it being DRM free and etc.. But now I, and others that read this know now. =)
I know I HATE it when I buy a retail game, and then forced to use Steam to play it. Not against Steam, as I have over 300 games from them. But when I buy retail, I expect to be able to play on Mars if I wanted to.
Silly that some of the mod creators felt like they needed to "police" the game. The minute GOG offered Terraria, I bought it right away, so that I do not have to play a cracked version at dialysis even though I bought the Steam version. Steam is blocked and bringing your own laptop is discouraged wanting you to use one of their 3 available there for patients that you cannot install or augment anything. Just web browse or play freecell. For a few years they even had YouTube blocked among other sites. Of course, some of the patients figured out ways to circumvent some blocks only to get those blocked later.
My apologies for the rambling going on and on.