It's not any grief, and only a *tiny* bit of confusion. Mounting is for data. Files. Folders. Bits and Bytes.
A Data CD/DVD Primer (in case there is continued confusion)
While it's possible to put almost any data filesystem on a CD or DVD, the three most common data filesystems on optical media are CD9660 (by far the most common "data" disc format), something newer called UDF, and a "bridged" filesystem which is partially CD9660 and partially UDF. The bridged filesystem is used in the DVD video format.
Most data discs use CD9660 file systems, with "extensions" to support the needs of the intended OSes -- Rock Ridge for Unix and Unix-like systems, Joliet for Windows, and HFS (Hybrid) for Macs.
On OpenBSD, there is the built-in
mkhybrid(8) program for building CD/DVD data file systems. I prefer the mkisofs program included with sysutils/cdrtools.