Well, you can't cure ignorance, as cruel as that sounds just be real for a second. If a person chose to ignore the message that he/she definitely notices when joining the game it's not your job to go out of your way to make features for such people.

The thing is, this feature would create images on your system, and if nothing changes it would save them as .bmp which might be a problem to some users in terms of storage (I think Sir already mentioned this though). Also newer toribash features are known to be barely working and buggy as hell so I feel like this would be more of a problem to maintain it than implement it. I think it is not even fair to compare ease of implementing few lines of text and a feature like this. If you think that they both are similarly easy to implement I got no words really.