It's 10x more efficient
for human purposes. It's not a 10x more efficient mechanism in general. Evolution has no need to produce 10x more rather energy-expensive molecules than it needs, so it doesn't produce bacteria that do that.
Which is also the answer to everybody else wondering about what happens if this gets into the biosphere. Well, have you ever been walking in a relatively natural forest area and come across the sad sight of a natural clearing being totally dominated by wild broccoli plants? No, you never have, because broccoli is completely incapable of outcompeting any natural plant. Broccoli's genes put way too much energy into producing that big beautiful edible bit that all of its competition puts into offense and defense. Similarly, the answer to the question of what happens to bacteria that pours its energy into producing alcohol while its competition is pouring its energy into producing offspring is that if you blink, you'll miss the death of the alcohol-producing bacteria. They're not going to take over the ecosystem. In energy terms you probably stand a better chance of seeing broccoli sweep the meadows of the world than having this bacteria survive in the wild.
(And when I say broccoli, I mean something like what you'd buy in the store. Not merely a rapid reversion to its historical ancestor, which could actually happen, but actual proper broccoli.)