You might think that it means Apple is going to sue us every time we mention an apple, but according to the website that seems to be related to the posters, it is all based on a bizarre pseudo-legal claim, with no basis in law, that your birth certificate means that you handed over your name to the Crown/government, and it is then illegal to use your name without their permission.
There have been absolute shedloads of discussion of these things on the internet - plus quite a few websites making the claim supporting this idea that you do not have legal ownership of your name. I'm not going to link to these for reasons discussed below, but you can easily find them if you wish. As far as I can see there can only really be three reasons behind this.
One is that there is a very rich conspiracy theorist who genuinely believes that the legal registration of our names is a state control measure, and we should therefore identify ourselves as WibblyWoo73, justifying all those silly online names we give ourselves before we get older and realise how stupid they look.
The second is that this is a vast clickbait/phishing programme, and the whole idea of it is to get you to look at one of their websites, which then plants something malicious on your computer. If so, it's a very expensive way to do it, compared with sending out spam emails or putting fake giveaways on Facebook. The only thing to be said for it is that spam tends to capture the naive, while this approach will catch the curious, and the two sets are by no means identical, so it would widen the scope of the scam.
And the third? It's the most expensive practical joke you ever saw, and all of us who are writing about it are falling for it hook, line and sinker.
This has all been going on now for some time - we had another outbreak of posters last year. Apparently the Advertising Standards Agency thinks the posters are harmless, so they may well continue for some time to come. Silly season fun, or dangerous misdirection? You pays your money and you takes your choice.
* I did not take this picture while driving.