Lumberjack Cake?

Today I made Lumberjack cake - following the tried and true recipe on the Women's Weekly recipe card - it's one of my staples. Always a success, always enjoyed and easy enough to put together for afternoon tea so long as you don't leave it too late to prepare the dates. But why is it called Lumberjack cake?
Searching the Internet doesn't provide any clues other than that it is sometimes referred to as 'Loggers cake'. But what does it have to do with lumberjacks or loggers? The specific ingredients which make this cake different to any other - dates, apples and coconut - aren't specific to lumberjacks, are they? Nor are they likely to be the sort of staples you would expect to find in a logging camp, are they? It's all just a little bit mysterious.
Even Python lumberjacks don't eat cake, well not on Wednesdays anyway.

I'm a Lumberjack and I'm okay,

I sleep all night and I work all day

I cut down trees, I eat my lunch

I go to the lavatory

On Wednesdays I go shopping

And have buttered scones for tea