here are two main reasons why folks love front loading cargo bikes; control over the load and an eye on the cargo.  

The Supermarché is designed with a super low front rack offering a extra low center of gravity resulting in better control over the load; not to mention a huge carrying capacity.  Haul up to 220 lbs. in front and 80 lbs. on the rear rack.  

Second, for folks hauling kids or dogs or precarious cargo, having a view of the load is essential.  You can play referee and provide snacks upon request without stopping.