Is the Location of a Flower Vase More Important Than We Think?

Sometimes flowers seem to wilt even when they have plenty of water. I am wondering whether the environment around the vase could be one of the reasons.

I would particularly like to know about:

1. Keeping flowers away from direct sunlight
2. Avoiding areas near heaters or warm appliances
3. Whether cooler rooms actually slow down water loss
4. Why some people recommend keeping flowers away from fruit and vegetables
5. Whether placing flowers in a refrigerator is actually a good idea

While researching How to Make Flowers Last Longer, I found that vase placement can be an overlooked part of flower care. Has anyone experimented with different locations at home and noticed a clear difference in how long their flowers stay fresh?