(unless there was a trend ancient poets adopted of heavily employing repetition as a rhetorical technique
In her translator’s notes, Stallings mentions the repetition:
“Writing in the epic tradition of Homer, Lucretius occasionally repeats phrases, lines and even passages verbatim. Within the constraints of a rhymed translation, this effect was not always possible to replicate, and so I sometimes make use of variation where Lucretius uses repetition.”
Lucretius. The Nature of Things (Penguin Classics) (p. 238). Penguin Books Ltd. Kindle Edition.
So, she seems to think it was a poetic device in the Homerian epic tradition ...