Unnecessary; Unjustified

According to the critic, the film was filled with gratuitous violence that served no purpose in the plot.

Aggrandize

1.To make greater in power, influence, stature or reputation

Ex. Sheldon aggrandized his business by acquiring another company.

2. To exaggerate, or make something seem greater than it is.

Ex. Roberta aggrandized her accomlishments by claiming that she was the top seller in the company. 

Exorbitance

1.Extreme, unreasonable expense or price; being beyond reasonable or proper limits

Ex. My dad was shocked by the exorbitance of the prices at the fancy French restaurant.

1. Trying to seem important characterized by pretended grandeur

Ex. Mario's grandiose talk of his high power connections in Hollywood couldn't hide the fact that he was a struggling actor.

2. Grand; Magnificant in size, beauty or scope; impressive

Ex. Perry admired the grandiose doorway of the mansion with its huge, carved pillars and ornate stone work.