It's a joke about sending an image with 56 different styles of letter K, instead of 50k in-game c.a.sh.
I think the "asking for in-game currency" trend might be universal for every online game there is.
But it looks like in some games (Roblox for example), the topic of begging seems to be quite big, quick Google search showed many popular YouTubers making videos around this topic and getting lots of views, so the idea gets promoted even more.