There are a total of 6 BLAST Soda Cans available on Halo 2 Anniversary MP maps. It is recommended that you use a Sniper Rifle to destroy them, and they are easily done in Custom Games.
On Shrine, it can be seen with a Sniper Rifle by standing on one of the carbine spawns, and looking to the left of the base where players will find a temple. On the top of the temple, the can is standing. It can also be seen in the video below.
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2:54] - Shrine