As someone who once spent nearly a hundred hours to defeat a $20 Department of Labor claim, mainly to fight the precedent, I can sympathize 100% with Wal-Mart spending millions to fight a $7,000 OSHA claim. Note that despite all the OSHA wailing about not understanding why Wal-Mart is fighting so hard and causing them so much trouble, they admit at the end that they are trying to set a precedent for future actions.
For several years I worked for Emerson Electric, which among its many divisions owned a ladder manufacturer. If there ever was a product that simply is what it is, totally WYSIWYG, it's a ladder. But it turns out in this age of personal responsibility that anyone who ever gets hurt using a ladder, usually doing something stupid, will sue the ladder manufacturer for his or her injury. Emerson fought every one, all the way to trial and sometimes appeal. Lawyers said they were crazy, that in any given case, it would be cheaper (considering legal fees) to just settle. But Chuck Knight (Emerson CEO) knew that these were not individual cases, they were multiple events in an ongoing "game," and game theory gives a different answer. Fight enough of these, and tort lawyers looking for a quick buck with little work and cost will choose to spend their time elsewhere.