Chains seem to never do the original, but small, locally owned restaurants often do, at least in my experience.

Wow, you learn something new every day. I didn't come across it the couple of times I've been over there. I suppose in TV and the movies we always hear the "correct" version (even in a public setting) because they've paid the money to Warner to be able to use it.

I've heard the Happy Birthday song in a Hard Rock Cafe. I suppose they paid for the right to do so.

Generally true, but I've actually been hearing more and more of the actual song lately.