The gas that gets pumped into your house has no smell. This means the first sign you get that you’re inhaling gas is a lack of oxygen to the brain. To correct that problem, companies use a chemical characteristic of badly made wine.
I learnt of mercaptan when dealing with propane. I never knew it was used in wine production, but I guess it’s not the sort of thing you’d want to show people on a tour 😉
In the theme of misheard lyrics:
Insane in the methane: