There are countries where people have lunch at 12:00 and countries where they have it at 14:00 or later. Dinner and bed time are set in consequence. For the people in those first countries it makes sense to never have DST. For the others it would make sense to have double DST. We can argue that they could shift two hours backward with no consequences but cultural habits are hard to change (I live in one of those countries.) Having light late in the evening (22:00) is great if people are still out. Nobody use sunlight at 5:00 if they're sleeping.