Conversely, sometimes people wear dark-coloured, tight-fitting, full-length clothes and then complain about the heat. I understand why in certain situation someone might not want to wear tank tops or shorts, especially if they (think they) are not very conventionally-attractive, but lighter colours, looser-fitting clothes would still help.

Combining the two, I've meet at least one person who would dress more or less the same way in January and July and complain both about the cold and about the heat.

EDIT: I meant “I understand” in a descriptive way (‘I think I know what's going on in their minds’), not in a normative way (‘ugly people had better please cover their bodies’). Body policing is evil and I'd rather not do that.