It is not that it is common to have songs with eight chord changes per 4/4 bar, throughout the song. In fact, I cannot think of one.

However, it is not so uncommon that in a particular measure of the song, one might need more than four chords in that measure.

Passing chords, for example. On beat four of a song, there might be eighth note chord changes, two chords in that beat, followed by a new chord in beat 1 of the next measure.

Or, there could be an important part of a song, where there are quarter note triplets on beat three and four, a new chord for each (could also be considered passing chords), I. E. three chords evenly spaced over two beats. One should be able to do that without complex workarounds, and also with RealTracks.