What's up with these boxes?

I have seen these boxes on tons of ads on BP (not that I actually see any BP girls, just like window shopping there) and always assumed it was some pimp who was textually challenged, using some strange font or emogee. Now I am seeing them more and more here Ex. 🎵🎶 Lyric 🎶🎵

Can someone explain why these boxes appear?

People attempting to copy and paste ASCII commands that aren't supported. At least, that's my assumption, I could be wrong.

Non standard Emoticons from different devices, in your example I see musical notes (iPad/safari) but bet If I look from a different device/browser I will get a different character mapping ex []