rgd1101 :
No. mac address are not broadcast
Technically, they ARE but they're not going to show up beyond your local network as IPs are tunneled and NATted. Here's part of my local ARP table on my workstation and you can see a section of the network-bound MAC addresses...
192.168.1.100 f4-0f-24-95-f4-cb dynamic
192.168.1.101 80-e6-50-01-78-a8 dynamic
192.168.1.103 dc-a4-ca-5f-26-4f dynamic
192.168.1.109 00-15-5d-41-90-03 dynamic
192.168.1.113 00-22-2c-80-8a-3b dynamic
192.168.1.116 c8-3a-6b-1a-80-bd dynamic
192.168.1.117 00-15-5d-41-90-02 dynamic
192.168.1.119 60-a4-4c-a7-3d-6d dynamic
192.168.1.120 7c-bb-8a-87-20-fc dynamic
192.168.1.121 d0-03-4b-40-a3-90 dynamic
192.168.1.124 4c-34-88-e7-0c-d9 dynamic
192.168.1.134 08-66-98-a0-46-9d dynamic