When you have a corporate crime, you need the ability to surgically penalize the guilty parties and minimize the collateral damage.
For a small public or private company this might involve all the share holders and the Board of Directors and the employees or just a few of these individuals.
For a large national or global company, it is much less likely to involve everyone but rather a specific few, although numerically the few might well be numerically more than all the individuals in a small company. This is because larger organizations tend to have processes and procedures in place to prevent illegal activities and if there are simply too many individuals involved then it becomes impossible to keep something hidden/secret if the illegal activity is widespread.
While we often think of laws as defining what is good and what is bad — it is probably better to think of laws as the current rules that we operate our society by.
Some of these rules do separate good from bad, some separate safe from unsafe and others are simply arbitrary limitations that are set.