Analogies are useful to illustrate a concept which isn't so clear in the issue at hand.By not lobbying they could at least claim ignorance or ambivalence or something, but knowing it's wrong and still taking it is just greed for the sake of greed.
Here's another analogy I just thought of. It's like if someone was drowning and they're up there throwing buckets of water on them, and they say, "This is kind of messed up, we should stop", but then they just keep going with the buckets and you're like, "those are some good guys right there, by telling people they should stop, they're helping that drowning man they're dumping water on." They're not altruistic, they're just being dicks.
Careful, this is approaching the red herring fallacy.
But this isn't necessary here.