Today around 12:00pm EDT, a post was uploaded to r/whenthe by u/concussionmaker_91 about how despite their multiple privacy measures, Reddit was still able to ping their location and show them an ad about a business in close proximity to their house. Then, in less than 2 hours after the post when live, their year old account was permanently banned. 
Redditors in the comment section used a website called SnooSnoop to see if this account has done anything malicious in the past that may be grounds for a ban only to find nothing. 
I don’t think this is a mere coincidence and some comments I read on the post may be there to dismiss the situation.
I’m currently working on archiving the post and comments in case Reddit decides to try and erase this entire situation from the web, I’ll attach the files when I do.
MAC address is in the data link layer of the networking stack, and would only be seen by other devices on the same network as you. This isn’t visible to websites you visit (unless you’re on the same subnet), and as TCP packets go through network hops, the MAC address is replaced with with the routers MAC address for each hop.
The reason for MAC address randomization (standard on iPhone and Android) is not for anonymity to the websites you visit, but is there to anonymize the wifi broadcasts in your general vicinity, like a 30 meter radius. The MAC address is randomized so that broadcasts to check wifi networks while you’re out and about can’t be used to track your physical location.
I’m speaking from the point of view of the app you gave permissions to collect your hardware data. Y’all are talking like I think a MAC is transmitted over tcp. I don’t need an intro to OSI. Those apps use the hardware data to know if you’re using Samsung, LG, Apple, etc and they store large databases of MAC addresses on individuals. They can even build a local hardware profile to see if you sold your device, to whom, and what device you replaced it with.