We get posts here too, and on Reddit

The posts here get reported and removed very quickly, sometimes within minutes of the account being created or the first post.

I searched Reddit for the website they were linking and saw the spam posts on Reddit have been up for months.

Few possible differences:

• We have a better ratio of users/moderation, where the lower volume of posts means everything can go through human moderators

• Our users are more actively trying to keep the platform good by reporting spam

• The incentive here is to create a good online platform. The inventive there is profit. The priorities are different as a result