Why does everyone think they’re dehydrated?

I swear 75% of the people lately blame everything on the fact that they’re dehydrated. Or vomit twice and are adamant they need IV fluids.

Is this a thing elsewhere? Convincing these people they’re not going to dry out like a 1-use contact left for 5 minutes on the bathroom counter is such an uphill battle, but we are busy and I don’t feel like wasting the resources of a busy ER when people are perfectly capable of drinking their own water!