I do think though that in life having a Plan B is useful. For example, you are on a trip with kid(s) and something unexpected arises, as can often happens with kids, you need to not only have a Plan B., but more importantly we need to teach our kids that they have to learn to be flexible in life, because the truth is, things don't always work out EXACTLY as we planned, but most often, they work out the way that they (((should))).
Being inflexible is not a healthy model for kids. "It's my way or what"??...I can't deal with real life?? I hate the world for not delivering everything I want in the way that I want??? What??
So, I think it's healthy to differentiate the fact there are different circumstances in life where having a Plan B is actually a good thing, a wise thing, to have in place...That's my take at least. :)