When you find an iPhone and wipe it clean does that allow you to use it?

I found an iPhone 7plus and I looked all over for the owners for about 20 minutes. There was a password lock so I couldn't gain access to the device. Convinced that I would never find the previous owner, I reluctantly removed the sim and wiped it clean. I check the imei and it has not been reported stolen. Since wiping it clean I now have the ability to set it up as a new phone, so I'm about to activate it using a new SIM card. What can happen?

Yes you can and you in the clear too especially if it's a t-garbage and at&t phone. Make sure you restore it to factory settings and erase all memory

There's a law in society called finders keepers make you the reaper

Nothing. You'd require the Apple ID & password to activate it.

Short answer: No.

Lang answer: About as much as finding a car and washing it does. So, no.

Even if you were able to activate the phone, as soon as it was reported lost or stolen, it would be shut off, even if it were a month later.

Also I call BS on you trying to find the owner of the phone. All you had to do was take the phone to an Apple Store or the carrier that was on the SIM card, and the owner would have been contacted and would have had their phone by the end of the day in most cases.