That's crazy !
I have three Fathoms - NONE have any purple on the left hand side.
I have an original Fathom flyer. Again, no purple.
I'm one of CPR's biggest fans and I've bought 6 playfields and 4 backglasses, but I would be emailing them to find out why there is such a difference. One of the highlight's of Fathom, is the different shades of Blue. There's no shade of blue that is purple !