Brand awareness ads. Pretty much it’s irrelevant what you say about brand ‘X’ as long as you bombard gullible observer with ‘X’. Then buying ‘X’ would be more familiar choice for millions than buying ‘Y’ or ‘Z’.
I think the Parent was actually advocating surgical PPC management of the style patio11 has written about extensively.
Other reason to use it is when you dont want to be screwed by fake clicks, and are 100% sure people will find your product anyways and buy it.