Really?? I'd argue that Apple's reputation is based on slick, industrial design using (at times) fairly expensive components with an emphasis more on form than function (IMHO) and embarrassingly poor QC. I've gone through two iPod Touches, and two iPhone 3Gs - of those four devices, half had large particles of dust under the display, and three had manufacturing defects in the outer casing.
Still, you have to draw the line somewhere. I don't think light showing through a thin white plastic case is anything to get your panties in a twist about - it seems like a perfectly normal thing to me. Bright light + thin plastic? Yeah, I expect to see some bleed. Wouldn't anyone?