The reasons for censoring the scenes in Dragon Ball are similar to the Looney Tunes "Censored Eleven." (Read:
http://en.wikipedia.org/wiki/Censored_Eleven) Both are extremely offensive to the ethnic groups that they derided, and while Dragon Ball was less so, the lesser of the two evils is still evil. I'm not claiming that Akira Toriyama maliciously made the characters to offend, nor do I think that he is a racist man. One must understand the distinction between "racist" and offensive." While I don't think that Mr. Popo and other characters were made to promote a racist worldview, it's still clear to me that they are quite offensive. There is one distinction between the Looney Tunes "Censored Eleven" and Dragon Ball in that most (
most) Looney Tunes fans don't scream "WHAT A DISCRETION TO THE SERIES, HOW
DARE WARNER BROTHERS REMOVE THESE EPISODES?" Indeed, there is a stronger case to be made for the "Censored Elven" because they were extremely indicative of the times that they were released in, and as such, a rather important part of cartoon history. Should they are on TV unmarred or in some cases, even at all? Absolutely not.
Unlike Jinx or Oil Man, who kind of maybe look like racial stereotypes if you look at them from the right angle, there are several things that make Mr. Popo extremely offensive to many different ethnic groups. His behavior, as well as his appearance, shows this. I really don't understand why people think it's so unfathomable that Viz made this slight censor.
Aside from that and some aspects of the female and male form (all six panels in the entire series containing them), that's really all they visually censored, isn't it? (Censoring the guns was ludicrously silly, I will agree with that, it's an extremely violent series as is and I don't really see how guns would affect that too much).
This rant is a little long, but I'm getting sick of people whining whenever the words "Popo" and "Viz" are uttered in the same sentence.