[FungalRaincloud]

Typically, the MAC address is not public beyond the next router. Software could intentionally leak it, but I don't think that's likely on a system built for anonymity. However, it is possible that, should your traffic get traced to your true IP address, interested parties would attempt to then trace it to an individual. Any router you connect to could be storing access logs (or even passing them on to the next connection point) for a long enough time that they could narrow down which MAC the traffic came from. If they have you on camera, and the recorded MAC matches your PC, that's a bit more evidence. Sure, you could potentially fight it in court (MACs can be trivially spoofed, after all!), but why bother taking the risk?