再问问just as..so..

请教一下，

just as....so...中的so是否能省略呢，为何题目中未划线的原文常会不用so（如下例），那我们自己选择是是否一定要有so呢

eg.Despite the growing number of people who purchase plane tickets online, airline executives are convinced that, just as one-third of bank customers still prefer human tellers to automatic teller machines, many travelers will still use travel agents.

many travelers 前却没有so....

谢谢指点！！

这题好像不是just as....,so结构。just as是比较。不过在just as so结构中，so是可以省略的。