Theater ticket pricing is a good instance where pricing varies with demand.
Fridays and Saturdays (opening nights for most movies) the tickets are charged the max (here locally it is $10 per tix), on rest of the days from Mon till Friday 5pm it is lower ($5 per tix).
There are enough customers willing to fill theaters paying for opening nights as the movies do their best to line up demand for Fridays and Saturdays through intense advertising campaigns. After that it is a diffusion process that proceed more or less by word of mouth.
Pricing might be refined to get better revenues if it were not for the simplicity of a two tier system.