no
Yes you will need to refrigerate after opening, but it doesn't need to be refrigerated if still sealed.
Raw maple syrup - such as you would buy at a country stand where they make it on the property - should be refrigerated, yes. Store bought maple syrup does not need to be refrigerated, in fact one well-known brand states on the label: "Refrigeration not necessary". Unless you use your syrup within two or three weeks after opening, it helps to refrigerate it. I've had open syrup develop a type of mold after a few weeks even though it was labeled not to require refrigeration.
Yes. It really should have been refrigerated before opening, too.
No, it doesn't need to be in the fridge. And being at a colder temperature will make it somewhat harder to pour out of the bottle. It's fine to keep it in the pantry and it's also great if you warm it up first.
It may not have to be refrigerated after opening - but it will probably retain it's moisture and flavor better if it is. If the bag recommends refrigerating after opening, then do so.
Yes. Homemade marinade should be refrigerated, and purchased marinade should be refrigerated after opening.
Yes. Homemade marinade should be refrigerated, and purchased marinade should be refrigerated after opening.
Yes, generally hummus is sold as a fresh food.
Provided the package hasn't been open, you may store the syrup on a shelf at room temperature. However, once you open the syrup, it needs to be refrigerated until used up.
I would suggest you refrigerate the opened container. If it was in the refrigerated section when you bought it, keep it refrigerated. If it was not in the refrigerated section, check the label for instructions like "refrigerate after opening". Absent those instructions, refrigeration would probably help protect flavor even if food safety might not be an issue.
Yes, since there are no natural preservatives in pesto, it should be refrigerated.