Scientists create bugs that eat waste and excrete petrol

This headline so reminds me of a poem titled "Annonce" ("Want Ad") which Johann Wolfgang von Goethe wrote A.D. 1811:

"Ein Hündchen wird gesucht, das weder murrt noch beißt, zerbrochene Gläser frißt und Diamanten scheißt."

Roughly translates to:

"Looking for a doggy which will neither snarl nor bite, broken glass shall be its food and diamonds be its shite."

I don't understand the last two paragraphs (before "Power Points").... the article is mentioning "for the greater good" and some counter-arguments to points that haven't been made in the article itself! The benefits of their technology is clear, but they're defending it against arguments that have (presumably) been made without telling us what they are...

One potentially untapped source of biomass might be grass clippings. It the tanks could be small enough to be operated at the household level, then perhaps one enterprising neighbor could buy the neighborhood detritus or offer to convert it for them.

Even if it's not competitive price-wise there is significant value for (some) people in feeling environmental; burning carbon negative gas in your car from your yard would probably fit that category.

It's quite an extraordinary achievement, but a lot of articles I've read on the Internet reporting these extraordinary break throughs in tech/medicine/health/etc, they never seems to materialize. The ground breaking changes just fades. I've lost faith. I will only believe it when I see it.