IS THIS FOR REAL ?

I can't help but think of my brother John as I write this. Without going into too much detail he has a habit of letting rip at the most inopportune moments.
I took this picture from the back of a taxi last Friday evening. The sticker, as you can see, was placed on the back of the headrest. Is this for real? Do Bangkok taxi passengers need to be pictorially told that farting is not permitted from the confines of the cab? Or is this just a taxi driver having a laugh?