Are they Trolls or...

What is the most confidently incorrect thing that you've seen someone say about TLD or wilderness survival?

I'll give two examples:
1. I had someone confidently tell me that people regularly go a week or more without water in non-survival situations.
2. I witnessed someone suggest that scrap lead should wash up in beachcombing areas... They compared the weight of the scrap lead item to the weight of fish.