Should I be insulating my house to save energy even if I lived in a warm country? See, this sound ridiculous

I'll bite - it doesn't sound ridiculous because it is highly likely that there is going to be power hungry air conditioning equipment in use. I think it's an example of an unfortunate phenomenon where if you deviate from the accepted cargo cult practices you run the risk of missing some detail and making things worse, at which point you get the blame, but conversely you don't get the credit for doing things better than average. In fact it's likely there is a peanut gallery just waiting for you to make a mistake so they can punish you for being a renegade.