There are many problems with anime dubs, but the biggest is that the concept behind them is fundamentally destructive to the original work. The original Japanese voice acting is just one part of the overall audio of the work, and as such it is carefully directed to complement the other parts, the soundtrack and effects/ambience. Replacing only one part of the original sound direction, no matter which part is replaced, destroys that complementary balance. It's like replacing the doors to a black car with white ones; the doors themselves achieve the same basic function, and some people may prefer white to black, but the car as a whole has obviously lost its balance and intended cohesion.
Of course, the execution of the localization is as much of a problem as the concept. The fact that anime (obviously) has been part of the social consciousness for so much longer in Japan than anywhere else means that it is a more widely accepted form of art, and therefore draws in considerably more money -- and, by extension, talent -- than anywhere else. Anime studios in Japan have a wide variety of skilled voice actors from which to choose, all of whom have the benefit of decades of history from which to learn. Anime has made huge strides in other markets, but it's still so new that these foreign talent pools just can't compare, and as a result, a small group of dub actors are responsible for the vast majority of anime dubs. (How many times have you heard Wendee Lee?) Smaller talent pools in dubbing invariably lead to homogeneity, to the point where arguments against dub actors on the grounds of pure talent, experience, union status, and so on aren't even necessary.
As explained by many others now, your definition of "weeaboo" is inaccurate. It's a nebulous term, but having an opinion on sub vs. dub does not make you a weeaboo. Believing yourself to be Japanese by adopting embarrassing mannerisms and catchphrases, overusing the most basic of broken Japanese language, and generally being unbearably overt about your fandom makes you a weeaboo.
Anyway, if we waste anymore time on "weeaboo," we'll be bankrupt by the end of the month [http://pbfcomics.com/71/].
Of course, the execution of the localization is as much of a problem as the concept. The fact that anime (obviously) has been part of the social consciousness for so much longer in Japan than anywhere else means that it is a more widely accepted form of art, and therefore draws in considerably more money -- and, by extension, talent -- than anywhere else. Anime studios in Japan have a wide variety of skilled voice actors from which to choose, all of whom have the benefit of decades of history from which to learn. Anime has made huge strides in other markets, but it's still so new that these foreign talent pools just can't compare, and as a result, a small group of dub actors are responsible for the vast majority of anime dubs. (How many times have you heard Wendee Lee?) Smaller talent pools in dubbing invariably lead to homogeneity, to the point where arguments against dub actors on the grounds of pure talent, experience, union status, and so on aren't even necessary.
As explained by many others now, your definition of "weeaboo" is inaccurate. It's a nebulous term, but having an opinion on sub vs. dub does not make you a weeaboo. Believing yourself to be Japanese by adopting embarrassing mannerisms and catchphrases, overusing the most basic of broken Japanese language, and generally being unbearably overt about your fandom makes you a weeaboo.
Anyway, if we waste anymore time on "weeaboo," we'll be bankrupt by the end of the month [http://pbfcomics.com/71/].