Well, as one who has unearthed all of my hardware synths again recently, let me explain why.
I love layered sounds, and having many things going on simultaneously. I only play as a one-person show, though.
I have my sustain pedal polarity reversed on some of my controllers so that I can hit a chord or a “one finger wonder” patch and let it drone on while I do leads and other stuff on other keyboards.
One thing I ran into with the all-software approach was that my computer’s CPU was becoming overloaded very quickly! (Alright, I do run some very CPU-heavy synths – Linplug’s Spectral, a few of the Roland Cloud classic emulations, etc…)
I’ve found that adding back my original Wavestation and the Wavestation SR, the Kawai K5000s, and the Ensoniq ESQm (and perhaps the Yamaha TX81Z will also follow) and forcing myself to use them more often took the load off the computer so that I could exploit those marvelous CPU-heavy synths and all the effects I could throw at those items!
Plus, thanks to Cantabile 3 as the central processing unit Deluxe, I have VST effects on those hardwre synths now to die for!
The result is I can have a huge amount going on at once.
That may (most likely) not be applicable to your situation, but it surprised me how much fun I’m having by not being limited by the CPU (and I have an Intel Haswell Core i7 4790@3.6Mhz with 16GB DDR3 1600Mhz RAM).
Terry