I can understand it seeming unnecessary to many people, however I am not sure any of us is qualified to truly make that call on a general basis without some evidence that, no, adding a piece of kibble does NOT contribute to calming/distracting the rodent and/or reducing the risk of a bite. Until you can tell me it doesn't, I think it's reasonable to posit that it does, and thus it seems like a reasonable, easy, consequence-free precaution someone might wish to take and in which I can find no fault.
Re teeth: I didn't mean it angrily at all. I truly meant that if that happened to you with an f/t rat, I would understand that if in the future you felt like you wanted to remove that risk (on an f/t rat - not a live one) and I wouldn't laugh at you for it because at the end of the day, you're doing something you feel reduces the risk of injury to your snake without harming, offending or inconveniencing anyone or anything else in the process.