I have never been asked for a copy of my diploma. Every time it has been my transcript and to have it sent directly from the school, not something I hand over.
Prior to my college career, I was asked for my diploma when applying for a job at a Dept. store (where I worked throughout my college career).
At my present job, I was required to bring my Diploma in, along with an “unofficial” copy of my transcripts. This allowed me to start without waiting 30 days for the transcripts to arrive from the college.
Guess it depends upon where you live, and what you do.