A little more context might help with all of these questions. What time period are we talking about (which Census?) What part of town did they live in?
For the driver/teamster, my first thought: is it possible that he worked "on commission" rather than for a specific Commission? Could this be a way of saying he was an independent contractor or got paid by the haul?
As far as the candy factory, a few possibilities come to mind. Bissinger's Chocolates is still in business, with a retail location on McPherson in the Central West End and a factory in the Midtown area on Gratoit Street. Here is some information on Bissinger's history:http://www.bissingers.com/aboutus/aboutus.php?page=history
And a blog post from a local resident who toured their current plant:http://nickidwyer.typepad.com/nicki/2011/04/in-case-you-miss...
Switzer's Candy was located just north of Downtown along the Riverfront. Here is their history from their current webpage:http://www.switzercandy.com/about/our-story
Finally, there was a candy factory in deep south St. Louis (possibly in Lemay, St. Louis County) which made SweetTrats. I don;t think they opened until the 1950's, and closed within the last 5 years.
Nothing comes to mind for "Mission Com House."
Hope this helps!