The "great" composers of the Baroque, Classical, and Romantic eras frequently wrote such chords into their piano compositions. One excellent example is the "Promenade" from Pictures at an Exhibition, by Modest Mussorgsky (public domain excerpt):
Right on the first line, we see the left hand is playing mostly in octaves. By the third line, both hands are almost entirely playing either octaves or chords containing octaves.
The reason for writing and playing chords like this is for the sound and sonority of these chord voicings (a voicing is a particular selection of which notes of a chord to play and which notes to double and which octaves to play the notes in).
In the first line of this excerpt, we can see that the melody starts as single notes and then the melody is repeated, but in the repetition, the melody is accompanied by right hand chords and a left hand bass line. This makes the difference between chords and single notes completely obvious. What is less obvious, but becomes clear if you listen to the piece, is that the more notes we add to a piano chord, the "bigger" it sounds. So we can take our music from small and quiet single notes all the way to large and majestic four (or five!) note chords in both hands.
The piano composers of the last four hundred years knew this and used variations in chord voicings constantly throughout their works. Today, piano players in pop, rock, and jazz also understand this and often use "big" chord voicings.
The reasons why big voicings are almost always bracketed by octaves is twofold. First, octaves are a comfortable distance apart on the piano to be played by the thumb and fifth finger of almost every pianist. Second, octaves have a sound that effectively accentuates either the top melody notes or the bass line without sounding muddy or unclear. Some musical theatre piano parts have baselines that are entirely or almost entirely octaves. It's a very effective and popular sound.
If you prefer a non-classical example, "You'll Be Back" from Hamilton has a gradual change from chords without octaves, to octave bassline, to chords with octaves and octave bassline for the big ending.