They don't. But if you get big and along the way in a throwaway comment on Patreon mentioned you use the Adobe Suite and other tools they'll look into that and if you don't pay they'll send a very stern letter demanding payment.

Generally for Joe Schmo if they're found out it stops at a letter demanding payment, and if you don't pay it likely won't escalate, especially if you deny the accusation. But for someone making a profit they'll get their money and it's a major headache and just not worth it considering you are making money far exceeding the rather small cost.

In theory, some busybody would have to report you for it.

It's encoded into the file itself which license you have

Your clients might be performing due diligence and ask you for copies of your licenses. Especially if they're in a jurisdiction that's more litigious than others

Instead of Photoshop, use GIMP. Instead of Premiere, use Da Vinci Resolve. Instead of After Effects, use Blender. Instead of Audtion, use Audacity.