Not in the same sense we consider them in traditional databases, used to find specific rows (needle in haystack). ClickHouse indexes are used to eliminate data pages to reduce IO for range queries, not to find specific rows by value.
Row-store indexes (indices?) are used for both. The first few levels of a b-tree index can be used for discarding/narrowing ranges, the leaf levels are for pinpointing a specific row.
What I think you meant to say was that Snowflake does not offer user-manageable indexes, not that they don't use indexes at all.
That’s still an index though isn’t it? Might work slightly differently, but the purpose is still the same.