To unduly harrass someone is to subject the attorney to a Federal Rules of Civil Procedure 11 sanction. If a judge decides that there is an abuse worthy of Rule 11, there are significant reprocussions to the attorney's career. It is more likely that K&K is working within the confines of what the Federal Rules permit.
See Rule 11.
To prevent firms, or more accurately, clients of those firms from taking legal action against possible patent/copyright infringers or trade secret misappropriators for cases like this is to impose a draconian overbroad prohibition likely to impede the protection of those with "real" intellectual property.
Com'on it's life. It's not perfect and it's sometimes abuses, but it works and may be the best way.