Okay, I know I’ll soon become known as the veggie doper, but I have this nagging question.
A few years ago, I “discovered” that if I put fruit or veggies (even the leafy kinds) in the refrigerator in a plastic bag with a couple of paper towels inside, they seem to last a lot longer. I have no idea where I got the idea. I may have read it somewhere.
Question #1 - am I nuts, or does this really keep the stuff from rotting?
Question #2 - why? (either way)
They soak of the moisture that otherwise condenses on the food and helps it rot. That’s why I reckon the Crisper in fridges should actually be named the Rotter 
I have some plastic bags specially made for the job that do a similar thing, but of course are reusable.
Like AndrewT said, it probably takes some of the moisture away from the veggie, which in some cases leads to quicker decay. I have learned that different veggies and fruits have different storage strategies. If you are interested, here are a few links that might help you decide if you want to put in the paper towel or not:
I don’t think it the moisture within the vegetable, but the moisture that evaporates out and condenses in the plastic bag.
It seems like the rot starts where the vegetable is in contact with the wet bag. If internal moisture caused the rot, it would begin inside the vegetable. Just an observation.
The paper towel would absorb that moisture, and also prevent the vegetable from making direct contact with the plastic.
It all depends on the vegetables.
I spent a while working for the largest grocery supplier in the USA, and toured a lot of their warehouses during that time.
The fruit & vegetable storage areas were divided into several huge rooms, with the temperature & humidity closely controlled in each one, depending on what was stored in it. For example, I remember that onions need to be kept comparatively dry, while carrots need more moisture. Bananas are completely green, and kept in separate airtight lockers. A gas is used to trigger them to start ripening, and that needs to be carefully timed so that they reach the store just turning yellow. Deliver them too late & they’ll go brown on you, and won’t be sellable. The gas that triggers the ripening is produced naturally by other fruits, like ripening apples. So you have to keep the air from ripening apples from getting into your banana lockers, or they’ll all ripen at once on you.
Many vegetables spoil due to too high humidity in the refrigerator; for them, putting a paper towel or something to absorb moisture (my mother used bread crusts) into the bag will indeed help. Other fruits & vegetables tend to dry out, because the refrigerator is not humid enough – celery & carrots, for example. Sealing them in an air-tight bag slows dehydration, and will make them last longer. So it all depends on the specific fruit or vegetable, and just how humid your refrigerator happens to be.
Just for the record, that’s ethylene gas. It’s also used to ripen tomatoes. The tomatoes produce it naturally, but artificially produced it turns them prematurely red.