Using commercial software without paying for it is, in general, stealing.
But here are a bunch of things that are not stealing:
- Using commercial software on a country other than where it was made available for sale
- Using commercial software after the vendor no longer wants you to
- Using commercial software in ways the vendor doesn't like, such as on a device the vendor doesn't approve of
- Using commercial software on multiple devices, provided you use it on only one of them at a time
- Making a backup copy of commercial software so you don't lose it if the original copy is lost
- Giving others a copy of commercial software that is no longer available for sale
- Modifying commercial software to make it more enjoyable, such as by removing user-hostile misfeatures
- Reverse engineering commercial software to learn how it works
Note that several of these items (such as cracking cheat protection in a multiplayer game) enable you to use commercial software in a way that unfairly harms others (such as cheating in a multiplayer game). That's not stealing, but it is wrong in other ways.