Product placement or directors using kit for free
The main reason you see so much Apple gear is in the realm of photography and audio/video production, Apple rule the roost.
If your a director/photographer and need a prop, you will often use what's on hand like a MacBook Air, or iPhone/iPad because they are lying around everywhere on every set and photoshoot I have been involved in for the last 16 years.
Apple don't need to pay for product placement, they simply need to provide the kit.
The people doing the production will naturally gravitate towards using Apple gear because they use the stuff all day long anyway!
In Australia, you don't see that much product placement, but it is growing - thanks in large part due to the awful "The Block" renovation show.
Most directors I know are not interested in product placement - it devalues their art.
They are of course happy to use something for free, but that really is not the same thing.
On a side note, I manage IT for creatives - video, photography, advertising etc...
100% of my clients use Apple desktops/laptop and around 95% use iPhones/iPads.
Whilst Samsung might own the phone market, you would never know it if you deal with creatives all day!