Most modern dogs don't fetch without additional training. They play with sticks just like little kids pick up sticks and swing them around for fun. Dogs were kept around as alarm systems, pest control, and for their unbelievable sense of smell.

There is science that shows there may be a correlation between outcomes for hiring but most experts seem to think they are not accurate and the correlation with performance may not be due to personality, but how likely someone is to cheat to get the "right" answer for the test.

Its basically pseudoscience however it gives employers a way to discriminate discreetly so of course they love it.