I don’t find Tinderbox all that useful for this. It’s not a bucket-app, especially since “random notes” tend to want to be moved somewhere else eventually.
“Random notes” fall into two categories for me
First, text I need to stick somewhere for a while because I’ll use it later today. For that, I use nvALT, which also syncs with Simplenote.
For “random notes” that want to keep indefinitely I’ll use Day One because it has excellent capture features (extensions, services) on macOS and iOS. Notes exported as HTML from Day One look very nice when dragged into Tinderbox.