We don't treat it the same way we treat other profession activities. Even enchanters don't look at it properly.
To start off, stop with the silly comparisons to rolling on mining nodes. That doesn't work at all. The node has zero value without a miner. The drops have value without the enchanter. The miner creates value from 'nothing' while the enchanter adds values to something.
What does the enchanter do? They convert them into something with more value. This is what all professions attempt do. They take cloth or bars or gems and turn them into something more valuable than selling the mats to the vendor.
Somehow we got the idea that enchanting is different. We got the idea that just because they are in the group that they are obligated to use their profession for our benefit, at no benefit to them. Ever seen someone tip an enchanter for DEing at the end? I never have. How often have you seen an enchanter not even get a single shard? I have pretty often. They add value an get nothing in return. They aren't even given an advantage in getting into groups; it's not as if people are saying "lf enchanter for [instance]." I might have seen that twice in four years.
Can you imagine at the end of a run shoving a bunch of cloth into a tailor's trade window and expecting a robe in return? Sounds ridiculous, doesn't it? Let's say you even have the other mats and thread and all that, just because you like carrying stuff. Anyway, that's beside the point. You'd not expect free benefit from a tailor or alchemist just because they're in your group, so why expect anything more from an enchanter?
We don't call tailors greedy for refusing to turn out cloth into bags, so why do we attack enchanters who don't turn unwanted gear into shards? It's time we started either tipping enchanters or stop expecting them to do us favors just because they happen to be nearby.