No, the point is to selfishly profit-maximise. I'm not trying to be difficult in saying that. The thing you describe is not the intent, it's the hypothetical effect. It may or may not do that (I don't think it typically does, take toilet paper during COVID for example).
Yes, the point for the individual setting that price is to selfishly profit-maximize. The point for us accepting a system that does this is because it signals to other water-bottle-holders that there is a dire need nearby and pays them to meet that need.
I don't think the example of a meme-driven pseudo-shortage of a paper good during a once in a lifetime global pandemic (causing both supply and demand shocks and significant information problems) is a very good point.