In Queensland what damage does a cowboy beetle do in the garden?

I have noticed a lot of cowboy beetles in my yard this summer. I wasn't able to find a lot of information about them but apparently the grubs feed on compost so I assume that actual damage to lawn\living plants would be minimal. From what I can see they don't seem to appear on lists of insect pests so that's a good sign.

I'm working on the principle/assumption that if they were really dangerous to gardens then there would be a whole lot more readily available information on them out there. Including information on what pest control products to use against them.