I like this idea a lot. I'd love to see it implemented for scrap as well. The pea shooting can get a bit tedious when the peas in question aren't spawning fast enough to hold your interest (not to mention getting in between your turrets every damn time like they're magnetically attracted to that one spot *ahem*). Having a second "mode" would be a great way to mix it up and break up the tedium, not to mention the above mentioned conflict it would generate.
Plus shooting wrecked ships/stations/giant chunks of debris with mining lasers just sounds satisfying.