Why a platinum spark plug - AVH 2.0 Jetta engine?

A coworker of mine is at the 40K maintenance point for his 2002 jetta
2.0 with engine AVH. The manual states the spark plugs need to be
replaced and the correct plug appears to be
NGK PZFR5D-11 which is an expensive ( $15 per plug ) part.

Previous 2.0 engines such as AEG engine code 99-01 model year used a $5
plug (NGK BKUR6ET-10)

My questions are :

Why did VW change to the Platinum plug?
If this was for longer life, then why do they still specify 40K
replacement intervals?
Is there a spark plug wire puller tool on this engine?

Can the cheaper plug be used? I would assume not unless someone could
prove otherwise because I have observed that the coil pack is also a
new design. I am just puzzled over the need for an expensive plug.

thanks!
Mark