IPv6: what is the purpose of ff00::/8 multicast routes? [closed]

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On Android, whenever an IPv6 address is assigned to an interface, the kernel would automatically add a default multicast route (ff00::/8) through that interface to the routing table. These routes seem to conflict (same metric) and cannot be deleted. What is the purpose of these routes?

ip -6 route
ff00::/8 dev eth0  metric 256 
ff00::/8 dev v0 metric 256

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The same metric is a hint that actually it is the same adapter and eth0 and v0 are only separate interfaces on that adapter. In other words a broadcast on one is the same as a broadcast on the other.

IPv6 no longer supports broadcast and applications must now use multicast.