The monkey symbolism of Lord Hanuman is related to the notion that a human being's mind is ever active and never restful, hence the depiction of a human being with the face of a monkey. Furthermore, Lord Hanuman symbolically stands for pure devotion, complete surrender and absence of ego or the lower self. As the son of Vayu, symbolically he also stands for the subtle body consisting of the breath body, the mental body and the intelligence body. Here we explain Hanuman as the mental body in a human being.
The mind, being ever fickle, jumps from place to place, obtaining everything in its path and engaging in numerous activities that brings no peace to the surroundings. The mind can travel to any place and fly anywhere and cross to other parts of the world such is the power of the mind.
The mind can also expand or contract, and if it remains under the control of animal passions and sensory activities, it will become instable and devious. Hence, the mind of Hanuman is always under this fluctuation.
However, once surrendering occurs to the inner self and the mind becomes devoted unconditionally, the mind can obtain miraculous powers and perform stupendous feats like that of Lord Hanuman. When one's mind reaches this state in working for the divine, it helps the lower self (Sita) and Soul (Rama) to come together and become united.
Don't believe it. Monkeys are fun. Monkeys come into the village and steal stuff. Monkeys throw feces at each other and at people.