Regarding the recent removal of 173 spam games by Valve, I would like to point out that AchStats has tracked more than 260 spam games plus another 60 spam DLCs. You can see the list here (it's a long one, beware of loading time):

https://www.achievementstats.com/index.php?action=games#spam

More important, you might not want to touch them. Besides of not wasting your money on worthless spam, it is possible you get a lot of unobtainable achievements. Just minutes before being banned, the developer updated some of his "games" with spam achievements without making it to the depot builds, i.e. you're now stuck on a lot of dead cheevos in that case.