No! Steinberg have always put these files in the top level project folder, and it’s a pita for keeping tidy. I’d defo support a feature request to move these to sub-folders. And also at the same time keep all current Steinberg sub-folders (e.g. Track Pictures) in a single sub-folder to keep my project folder super-tidy!
BTW, .csh files are Cache files (not crashed files). They can be deleted because they’ll be regenerated when you open the project (I assume they speed up project opening).
I personally create a folder called Backups and move .bak and .csh files into there. I also incrementally name every project when I save it, so I don’t over-write any project. Then I move old versions into the Backup folder too.
There’s a chap who’s written a tool to tidy you project folder IIRC… You may find it at it his website, http://www.pendlebury.biz/.