Breadcrumbs or flour when greasing and dusting a cake form?

I unthinkingly followed a recipe for a type of chocolate cake where it said to dust the cake form with breadcrumbs after greasing. Unsurprisingly the toasted breadcrumbs were clearly visible on the outside of the cake after baking.

This wasn't a big deal and the crumbs were easy enough to brush off anyway, but it got me thinking: when is it better to dust with breadcrumbs and when is it better to use flour?

For my chocolate cake, if I'd stopped to think, I would have used a flour/cocoa mixture. If I were making a delicate sponge most likely I would go for flour there too.

What about breadcrumbs though? Perhaps the batter is less likely to stick to the form if dusted with breadcrumbs? Or would you use breadcrumbs to add a little crunch to the cake's outer surfaces (can't say I noticed any crunch myself).