If I'm logging upvotes on a post or comments on a blog, which is about as serious as 99% of these b.s. startups are doing, I think it's fair to ignore errors.
I do agree that this should be pointed out in huge blinking letters though, or be a driver flag that is on by default. The amount of people who don't know this about Mongo, but are still using it to store gigs of data, is horrifying.