You make some good points. We should not go overboard with alternate components unless there is concrete gameplay gain. So maybe we should avoid the different kinds of fur.

I still think multiple components are a net gain when the source components are fundamentally different somehow. Particularly in the case of "use snow or ice for loam":  Ice can be dug out and carried, while water needs a barrel. Using ice for loam is good because if you can find ice, you can create loam on a different production route in winter.

The case of sand for loam: It's probably expected because loam is mostly sand in real-life. It's also possible to have sand in the bucket because e.g. you happened to dig through sand when trying to fill it, but didn't think it would matter. Alternative solution: Change the bucket to create earth objects when you dig through sand or ashes. That solves the problem for the player without adding complexity.

So my suggestion: Allow the alternate components, but use them sparingly only if the source objects are actually very different.