simcity 4 and The sims 3 are two games I know off you can run without the Launcher. After you install both games you just simply delete the shortcut Steam creates for the games, go to their respective install folders, find the executable for each and create your own. This newly created shortcut for these two games won’t be tied to the steam client\launcher as if you installed them by disc. And you don’t even need Steam running in the background before you can run both games. 
2 Likes