Yes, Fermentis propagates yeast using a molasses-based medium. Fermentis and Lallemand both propagate yeast aerobically using a continuous process and a device known as a bioreactor. This process is very different than way you, I, White Labs, Wyeast Labs, and most of the brewing world propagates yeast. We use batch propagation where the glucose level exceeds the Crabtree threshold of 0.3% glucose w/v. Above this threshold, the Crabtree effect kicks in. The Crabtree effect causes yeast cells to favor reproduction via the fermentative metabolic pathway even in the presence of dissolved O2.
Reproduction via the fermentative metabolic pathway is significantly less efficient than reproduction via the reparative metabolic pathway. If we can hold the medium in a steady state below the Crabtree threshold, the Pastuer effect will kick in. What happens when Pasteur effect kicks in is that the yeast cells convert pyruvate to acetyl CoA instead of ethanol. Acetyl CoA is fed directly into something known as the TCA (Tricarboxylic Acid) or Krebs cycle where it is converted to energy.
If we examine this process from a chemical point of view, it is easy to see that carbon is more effectively utilized in the respirative metabolic pathway than it is in the fermentative metabolic pathway. To keep things simple, let's just look at the major compounds that are formed. Both metabolic pathways take in glucose, which has the chemical formula C6H12O6 (6 carbon atoms bound to 6 water molecules). The major compounds produced by the respirative metabolic pathway are H2O and CO2. The major compounds produced by the fermentative metabolic pathway are CH3CH2OH (a.k.a. ethanol) and CO2. As one can plainly seen, ethanol is a carbon-based compound. If a cell is excreting carbon, it is not using it for energy.
One last thing, yeast cells do not consume sugar. They consume carbon. Sugar is carbon bound to water. All of the sugars found in wort are multiples of CH2O. The simplest sugars are called hexoses because they contain 6 carbon atoms. Hexoses are monosaccharides. An interesting thing happens when two hexoses combine to form a disaccharide. A water molecule is lost. This loss forms something known as a glycosidic bond, which is a type of covalent bond. While the chemical formula for glucose is C6H12O2. The chemical formula for maltose, which consists of two glucose molecules bound by a glycosidic bond is not C12H24O12. It is C12H22O11. A yeast cell splits maltose into two glucose molecules by transcribing1 an enzyme that inserts a water molecule; hence, the term hydrolysis. Hydrolysis is the combination of "hydro" (water) and "lysis" (break apart). Hydrolysis means to break apart via the insertion of water. The formal name for mashing is the hydrolysis of starch.
[1] For curious, transcription is the process by which an organism's genes encode proteins. Enzymes are proteins.