Hectolitre is 100 litres, not 100ml, but hectogram is 100g, not 100kg? Very confusing!

I mean

    Hecto = 100
    Hectoliter = 100 litres
    Hectogram = 100 grams

    Kilo = 1000
    Kiloliter = 1000 litres
    Kilogram = 1000 grams

It doesn't look that confusing?

Well yeah, litres and grams are the base units. Just because 1ml is 1g of water doesn't change how SI prefixes work.

I would have thought if gram is the base unit for weight then millilitre is the base for volume, but I must be wrong