To elaborate a bit more on that (because I agree with you): selling cheesecake is not a crime, even though foods high in calories and sugar are known to cause obesity which causes premature death. It's the consumer's choice to buy these, but since they are recognized as potentially dangerous, the government does regulate the production of cheesecake. There are ingredients you cannot use, you have to disclose the ingredients you do use, and you have to include a nutrition facts label that shows how much sugar and how many calories are included in this cheesecake.

What VW did was like a cheesecake maker being told they're not allowed to use trans-fats, submitting their cheesecake to the FDA for testing to prove it doesn't use trans-fats, and then selling a completely different product on the market that does include trans-fats, but not printing that on the label.

You're allowed to sell cheesecake even if we know it's harmful, you just have to follow some regulations to make sure the harm is contained to a reasonable level and to ensure that consumers are well-informed of the risks they're undertaking. VW cheated the regulations and lied on their label. Of course they should be punished.