The main profession the article picks on - interior designers - seems to be misunderstood by the author. He incorrectly insinuates interior designers only choose fabrics and colors. In fact, interior designers are professionals who have completed training in space management, ergonomics and architecture. They are able to recommend structural changes that could, if designed incorrectly, cause structural damage. Interior Decorators, who in fact are NOT licensed, are limited to choosing fabrics and colors (so to speak). More info: http://www.schools-of-interior-design.com/Interior-Design-vs...
Some of his other examples:
Frozen desert sellers - I hate to bring out the '...but think of the children argument,' but seriously, do you know if the grungy dude in the van selling ice-cream to your kids knows how to handle food safely? Has a criminal record? Has 12 DUIs?
Firework Operators - their job is to set off large explosions close to large crowds, occasionally indoors. I, for one, don't have a problem making sure they know what they're doing.
So the author may have a valid point, but his poor choice of examples does not support his case well in my opinion.