More is better and it's even more true for pinball! Pinball machines actually started their scoring from hundreds of thousands, by lighting up parts of the backglass where the numbers were. This was followed by the now iconic electro-mechanical score reels, where at the beginning 3-4 reels were used to show your score.

But everyone loves bigger scores, so first one, then more static zeros were added to the usually 4-5 reels that were used towards end of the EM era.

But when we went to the atomic age and digital pinball machines, we couldn't just have less score, so the extra zero stayed and it has persisted from 7-segment era to the current games with huge, video playing TFT screens. The only outlier is Jersey Jack, who actually dropped the zero and actually score single points.