Maybe, but impact can also make a pretty viable case.

For instance, if you own a home you may have an easement on part of your property that grants other cars from your neighborhood access to pass through it rather than going the long way around.

If Amazon were to build a warehouse on one side of the neighborhood, however, it's not obvious that they would be equally legally justified to send their whole fleet back and forth across it every day, even though their intent is certainly not to cause you any discomfort at all.

So is negligence. Or at least I would hope so.

Wilful ignorance is generally enough.

So have the stressor and stress testing DDoS for hire sites changed to scraping yet?

The courts will likely be able to discern between "good faith" scraping and a DDoS for hire masquerading as scraping.