Tieing some notes of single-stemmed chords tends to obfuscate the visible structure. It partly depends on the instrument and its ways of attack whether you do that: for a percussive instrument, the ties may serve as a reminder to "retrigger as necessary". It also depends on whether your notes are intended as constituents of a harmonic progression or actually as voicing. When doing a piano reduction, munging orchestral voices in that manner is pretty customary. For polyphonic original piano compositions, it would be quite more unusual.
Basically, if you consider this multiply voiced music which you'd split to different singers/instruments in a consistent manner if you only had single-voiced instruments at your disposal, it tends to make more sense to actually notate stuff in a multi-voiced manner. Your example is a bit extreme in that regard: one would hardly ever write it in the first manner you show.
When the notes are more haphazardly distributed and a consistent voice distribution is not feasible (are you doing your listeners a favor, though?), the first notation frees you from having to think up voice distributions making notational sense.