Consumers will not voluntarily pay for what they can get for free and for which there is no exclusive title to the property being enjoyed. These non-paying users are known as ....

Free-riders.

The correct answer is Option (4) → Free-riders.

The situation described is known as the free-rider problem.

When a good is non-excludable (no one can be prevented from using it) and non-rivalrous (one person’s use doesn’t reduce its availability to others), individuals may enjoy its benefits without paying for it. Such individuals are called free-riders.

Example: People benefiting from street lighting, national defense, or public parks without directly paying for them.