Thank you very much jzimm. Unfortunately this topic wasn’t considered in snappy either. Thus I still haven’t found any chance or way to place different applications on different drives / volumens.
After all that years with GNU/Linux, I am still astounded, that people wonder, why that could be usefull. Most power users comming from windows wonder how that simple thing does not work on Linux.
So to answer your question: This is usefull to people who use a lot of large applications with lots of data. A simple example are gamers, where games can ammount to several terrabytes.
Or is there a linux typical work around that I do not know of? No need to answer that, since that does not apply this forums topic.
But I had wished for snappy to be more versatile, like having interchangeable locations for snaps.