Hello Vincent,
normally a single MAC address is used for all SVIs by a multi layer switch see the following for a C6500
Vlan1 is up, line protocol is up
Hardware is EtherSVI, address is 0018.741c.6740 (bia 0018.741c.6740)
...
Vlan606 is up, line protocol is up
Hardware is EtherSVI, address is 0018.741c.6740 (bia 0018.741c.6740)
The MAC address is taken from the block of MAC addresses you can see in the output of sh module
in some cases you may need to change the MAC address on a per SVI basis and this is possible (at least in a C6500)
Hope to help
Giuseppe