Real world Examples.

1. The comma should be a semi colon because it is joining two separate ideas. I think they used a comma because most people don't know the semi colon exists.
2. The sentence is horribly written and needs to be re-written. They are putting a comma after every word when you could get away with using out using any.
3.This sentence would be better like this "Deli-sliced Turkey breast with lettuce and tomatoes, topped with crisp, hot bacon, swiss cheese, and our tangy ranch dressing." I think that it could be completely re-written as a list with a colon.
4. Just remove the semi-colon. The worst part about this is they use 4 different typefaces and one of them is Papyrus. Don't use Papyrus.
5. "So we hope you enjoy our famous pies and appreciate the rich history and legacy that's still baked into each and every one." is the correct way to write the sentence. People tend to write run-on sentences and they struggle making the transitions in the middle of them.