Quoted from Yelobird:Parts would be the Primary reason! Most any business especially pinball can make 20-30% revenue on parts alone. Games cost money, parts make money.
Why make small money on parts and help your ex competitor machines stay operational ??
While its your core business to sell your own new machines and there is Sterns big profits ?
When there are no parts to keep bly/wms running, operators need to buy more Stern games.
Quoted from KenLayton:I heard that classic Stern IP went to Gary's ex-wife.
Also read something last year, here in a discussion when Mirco started making Stern repro
playfields..