Lerd0 frequently has a post on first page. Sometimes, just thanks, sometimes with a meme. But that's not all he does. He isn't systematic about it. He posts in other places. He contributes to the site as uploader and is a valuable(?) member of the community. He doesn't give the impression that he is farming likes. He really just wants to thank the share or post a meme that came to his mind at that moment. You can tell because most of his first page memes are not edited in later.
Now let's talk about rKnight. This guy probably uses a f95zone tracker or religiously refreshes latest updates to spot new game threads. Then he will quickly drop a "thanks for share" post to reserve his spot at the top of the first page. He then later goes back and edits his posts with a meme. The meme format is very predictable and forced. He will quote something in the OP and make a "joke" about it. You can see that almost all his posts are edited.
And you pretty much NEVER see this guy post anywhere else. Not only is he farming likes, we can assume that he is also conscious about his likes per post ratio.
I mean, he ain't hurting anyone, so it's no big deal at the end of the day. Caring about internet points to this degree is weird, but if it makes him happy, good for him. But the "tradition" OP is talking about is probably this like farming behavior by rKnight. Others occasionally post their memes when inspiration hits them, but only one person is a constant.