Restaurants : Foamy The Squirrel As someone who has worked in the restaurant business (as a server) and been subjected to the birthday shit, I also find the practices rather irritating.
And going to a customer while their mouths are full IS absolutely planned out: the idea for the business is that if their mouths are full, they can't really do much aside from nodding their head or give a thumbs up when you ask how the food is. I personally never saw the appeal in doing shit like that and therefore NEVER did it myself.
For the birthday thing, I was out of town at a steakhouse thing, and not only was there a customer there that had to endure the shitty birthday song, but they also had to wear a hat thing with antlers on it, and they made all the other patrons sing along (I did not). As soon as that was over, I turned to the person I was at the venue with and said "and this is why I don't tell people my birthday," and told them that if they ever embarrassed me like that I would walk out of the venue and stop talking to them permanently.
So yeah... TLDR, I totally relate to this rant haha