The shape of a dowsing stick is like wheel barrow handles:
https://appleofgodseye.wordpress.com/wp-content/uploads/2009/07/dowsing_21.jpg?w=584
(Note how new age that image from google looks, it's from a book cover about dowsing)
They all have wheel barrows, because they're all dowsing.
Dowsing is often done on a specific property, resulting in a circling of the property until the sticks point downwards.
I don't see an alternative explanation for the characteristics of the cartoon.
Why do you think they all have wheel barrows?
EDIT: Here's a Smithsonian Magazine article lamenting that dowsing was being used by "urban New Agers" on things other than finding water: https://www.smithsonianmag.com/travel/urban-new-agers-have-taken-over-the-art-of-dowsing-1-38424068/
That article is from 1996, three years after the cartoon, yet is based on the same premise: new age types, using dowsing for other things.
I think my initial interpretation has now been proven correct.