Bad translations

I don't speak Japanese, but I translate other languages for my work so I have a tendency to nitpick translations that apparently carries over into languages I don't understand. I have been watching the series in Japanese for the first time, on the Funimation website with their subs, and I'm reading the Viz translation of the manga along with it, so I get both the Viz and the Funimation translations. They're often radically different. Today, I read a bit of the manga ahead of time and I was confused because Bulma's last line in the top left panel of this image didn't make any sense.

"This bum doesn't do anything but work out! Just like his dad! Are all Saiyans like this?"

If she's talking about Vegeta, it doesn't make sense because she doesn't know his dad. If she's talking about Gohan, it doesn't make any sense because 1) Gohan doesn't do nothing but work out; 2) why would she care if he did; 3) it doesn't follow what Vegeta said.

The Funimation translation makes perfect sense, though:

"This guy doesn't do a lick of work. Just like your father. I wonder, don't Saiyans ever work?"

This is going to bug me. I feel like I have to learn Japanese just to appreciate my favorite show. It's silly; I don't watch any other anime. I'm just annoyed that Viz was so careless here.