Comment by mannyv

The reason you didn't just drop stuff in /usr/local? Space.

One of our devs was also a gimp contributor, and he dropped gimp into /usr/local and filled up the filesystem. And back then package managers didn't exist, so you had to read the makefile and hope you didn't remove anything that was shared

/opt/gimp or /usr/local/gimp.

Local because in some places they mounted an nfs share, and local was local to you.