I'm sure I recall seeing a few American breweries trying to grab attention with glitter beers last year. So, yes, they are (unfortunately) 'a thing'. The April fools is in relation to AHA adding them to their NHC style categories.
I've never heard of anyone making one on a homebrew level but I'm sure someone will have tried it.
Would it work on a homebrew level or would it settle out in the bottle with the yeast? It would have to be a glitterweizen or something to work if that was the case!
Seen the likes of brewdog and the like making these. Don't see the point apart from a marketing gimmick. At homebrew level I would just add the glitter when serving