Ugh, looks like ZVV published a new GTFS feed recently which has pretty bad data. For bus stops that have multiple locations (because the bus stops at different places in each direction, or for different lines) they use different human readable names with a meaningless numeric suffix.
And now Google has ingested that feed in the past few days, leading to the meaningless numbers being everywhere :(
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I recall seeing those numbers on some public documentation somewhere (maybe maps of more complicated stops?), so it might not be totally useless, even if confusing.
