Please, for the love of God, tell me I'm not the only one who experiences this...

Every semester I have students submitting papers, however, rather than putting their reference page at the end of the paper, they include the references in a separate document. Why would they do this? They've all had different English instructors, so it's not like there's one mastermind behind this all. Is there some reference page movement that I'm unaware of?

When I was taught back in the day we ALWAYS put the references in the same document, so I can't figure out the logic behind putting them in a separate document.

-Matt