Apple will have a record of all of these devices. The mobile devices will just get blocked from the networks by their IMEI, rendering them useless, and it would be trivial for apple to locate the devices based on their serial number at time of registration.
Always make sure newer-model tech gear bought online is legit, otherwise you'll probably end up paying robbers for these stolen, and promptly bricked devices. Avoid craigslist, agree to a demonstration, meet in public (and sometimes designated) locations.
I don't know about Macs but the stolen iPhone retails for $20-40 a piece for high end and new devices (iPhone X). These devices are iCloud locked and it looks like there is no way to unlock them unless you are the real owner.<p>This robbery just shows you why some people stay poor. It has to do mostly with short-sightedness.
Aren't the devices connected to some iCloud account or an equivalent software device lock?<p>Unless they gut the existing hard drives, can they really even flip these devices? Find My Mac might foil their plans.
... And yet no one did anything. I do not ask for some kind of anonymous hero but if you see a thing like that you should at least try to block them from running.