There are many people who think that there is no use for poetry. This is both for these people and for the people whom they attack.
In fact there are many uses for poetry. Rhyming poetry at least provides a way to communicate thoughts in a simple and memorable way - way that is much more memorable than prose and that as such creates a greater effect. It is an excellent device for communication of thoughts and feelings - both ones simple and ones complex.
Poetry is also wonderful for relationships and friendships. It provides a way to express one's feelings for the loved ones and lets them know how one feels about them. Not only is it an excellent aphrodisiac, but it also helps to make and keep friends. Expressing one's feelings for one's loved ones in poetic format serves to improve and cement the love and the frienships. This makes it valuable for both friendships and romantic relationships.
Poetry can also be a way to self-knowledge. It provides a way to express one's thoughts and one's feelings, which the mind can then make sense of after the writing is done. Poetry makes it possible to know oneself better and to thus become a more effective individual.
Also poetry is a path toward wisdom and insight. In poetry, the left brain and the right brain work together to arrive at wisdom faster than either modality acting alone. One poetic device toward that effect is extended metaphor, that compares different aspects of reality to see reality as expressed through both. With the intuitive and the memetic working together, poetry can achieve vast wisdom and insight; and that in itself makes it useful for discerning reality.
Finally poetry - at least good poetry - is valuable simply for this: That it is beautiful. It is a way to create something beautiful in the world and thus to add something good to the universe and the civilization. Good poetry adorns the civilization and constitutes its flowering and its completeness.
For all these reasons, poetry is useful and should be treated as such.