I found this:
If you navigate to this directory:
C:/Program Files/Steam/steamapps/common/terraria *
There will be an .EXE file named "Terraria" (Bet you didn't see that one coming)
If you boot up this file, Terraria will launch without having to have Steam open in the first place.
I feel this will be helpful to a lot of people who want to play without using the Steam program.
Leave a reply or a like, let me know it helped you!
* In a 64 Bit Windows OS, the path will be C:/Program Files (x86)/Steam/steamapps/common/terraria
Until a certain someone finally purchases the 4-pack I can't verify though.;
But the less than legal version runs without Steam ;)