A great deal of energy is involved in firing them, and chemicals used to seal them. The clay is dug out with massive machines, shipped worldwide, yada yada. Ceramics also aren't just pottery; they have many uses in industrial/manufacturing processes, and they're also used in electronics, skin care and a whole host of other things. They just wanted to fight and got mad that I was an autist who got excited when someone brought our food out on a VERY beautiful plate. They started in about how "real ceramic plates are bad for the environment." That kicked off a lengthy struggle session about how the food on the plate was way more carbon-intensive (you eat it once) than a plate that will be used hundreds if not thousands of times. And it was pretty. These fucks suck the fun out of everything, and they don't even know what they're talking about. "Well akshually glass is superior." and can be tempered with fucking lead for durability, boron trioxide, and sand, etc. They're prone to chipping, and just because you can see through them doesn't mean they're better (this was deadass one of their arguments. Their, btw. I learned they were nonbinary on our first IRL interaction. lol. God.) Nothing is "pure" in this world, retard. It's all created under massive industrial processes, and it takes a lot of energy to make each thing we use. I just wanted to eat my goddamn food and chill. And when they didn't know shit about shit, I patted their sad hand and told them, yes, maybe they were right, perhaps we shouldn't have so many plates in the world.
That was a mistake. Never placate them. No. Be the one that tells them no. Be the one that makes them go read a Wikipedia article and learn something if only to yell at you over text the next day about how ignorant you made them feel about their lack of materials science knowledge. We can fix them, one negative interaction at a time.