Sounds like in hindsight, it was a pretty straightforward 3-0 and would actually have been a great opportunity to get some experience with the buzzers?
Referees love to study form/league tables and use their experience with teams to predict how a game will go, but I'm sure I've heard more wrong predictions than correct ones. Two of my last games this season were supposed to be one-sided walkovers according to other officials I was working with, but neither of them worked out that way until well into the second half. And I also recall being recently warned by an AR that a team's striker likes to draw in fouls and go down easy - we got in at half time and I thanked him for pointing the number 9 out as I had been able to wave away a few soft appeals, to which his response was "oh no, it was the number 5 I was talking about, he's playing in midfield today"!
Anything can happen in any game. If you insist on waiting for the perfect opportunity to use them, they'll just gather dust in the bottom of your bag for years until you retire.