I feel silly but can't help it.

You don't need to feel that way!! I'm sure you worked hard to earn the money that you paid to buy the agenda, it's only natural to want to keep it looking brand new. But, on a more practical note, Vernis really is more durable than people give it credit for!
 
hehe, I used to do that with my vernis agenda too but it got annoying after a while so I stopped. Vernis is actually very durable, I have used mine for about 7 months without a dust bag and there's no scratches on it at all.