Corporations can’t commit crimes because they are just legal entities.

The US Supreme Court begs to differ:

• https://harvardlawreview.org/print/vol-132/corporate-personhood-v-corporate-statehood/
• https://www.npr.org/2014/07/28/335288388/when-did-companies-become-people-excavating-the-legal-evolution
• https://www.pbs.org/newshour/nation/corporations-people-doctrine-real-legal-concept
• https://www.americanbar.org/groups/crsj/publications/human_rights_magazine_home/we-the-people/we-the-people-corporations/

The list goes on.

[M]any things that you think are crimes (dumping waste, not paying employees, stiffing suppliers, accidents) are not crimes.

Again, the US federal and state governments would like a word. There's not a locale in the country that considers theft and intentional illegal pollution not to be criminal acts with fines and, for natural person, imprisonment as punishments. However, you are correct that accidents are generally not considered crimes, although penalties may still apply if they were the result of carelessness or neglect.