Sometimes the volume in movies can be unbalanced -- either too loud or sometimes too soft. I usually find myself fiddling with my aids in a movie theatre or a concert hall. In watching a film, if someone has hearing difficulties and also tends to lipread, if an actor turns away while speaking the viewer might not know what was said. Dialogue spoken too rapidly can be problematic, too. Some movies seem to favor dimly-lit scenes, which again can be problematic for those with hearing problems. Hearing aids are not good at sorting out sounds and muting sounds which are undesired, so if someone is seated in front of someone who is loudly rustling a bag or candy wrapper or rattling the ice in his or her drink, that can be very annoying!
Some people don't like hearing aids because they cannot correct sound distortion, they only amplify it. Depending upon the type of hearing loss, this may be a real issue for the user. Other people don't like the feel of having something in their ear, whether it be ear molds or something in the ear canal. Still others, as was mentioned earlier in this thread, don't want something external on their head, whether it be hearing aids or glasses -- heaven forfend, both!