It depends on the dubbing company. The usual expectation for them is that the dub will not be for anime fans, but instead broadcast on TV as a general cartoon for non-anime-fans. Thus they'll often try to de-Japan the program.
It's almost hard to believe that they're still doing that, but at the same time I can see it for anything intended for children and to be played on television. I've been buying up straight-to-DVD releases from RightStuf.com the past four years.
I think "Seven of Seven" is the last one I remember that outright rewrote a few lines and a scene for the dub, which was due to the scenes involving English language and humor based on that. For example, in one scene in Japanese, a little American girl says to the main character, "Are you ready?" and the Japanese main character says, "Yes, I'm a lady." For the dub, the little girl says "Are you ready?" and the main character says, "Ready for what?" I guess "Bamboo Blade" had similar with an English-speaking character in a couple of episodes, where they gave her a "gangsta" way of talking in the English dub to compensate.
For series intended for televised released, I do agree with you, SuricouRaven. Brock making donuts rather than rice balls, everything done to Sailomoon by DiC, the cut-and-paste fest that was the US Cardcaptor Sakura (which I've read about, but thankfully not seen more than half an episode of, as well as watching the first movie dubbed just to quality I thankfully missed out on), and the effort to remove religion from Saint Tail (a series which takes place in a Catholic school, with a nun for one of the main characters! And that series didn't even make it to television as intended, so it was a straight-to-DVD), those are definitely something unnecessary for some of them, and outright disasters for the rest.
Actually, with those series in mind, I'd add to your list of changes: removing religion, removing things that might upset religious parents (such as tarot cards), removing scenes with comic violence (such as Melvin in Sailormoon being hit in the face with a party streamer), removing "inappropriate relationships" (making Zoicite female, and making Neptune and Uranus cousins in Sailormoon), and trying to change the target audience to increase viewership (making Cardcaptor Sakura into a series for young male viewers.)
For straight-to-DVD series that were clearly never intended for television release (as far as I would imagine), however, I know the next time I watch "Petite Princess Yucie", "A Little Snow Fairy Sugar", and "Bamboo Blade", it's going to be a coin toss to decide which language to listen in, because the dub is that good.