These are petty, spiteful behaviors. And, none of the tactics work to the other side's advantage either. These behaviors fan the flames instead and cause bad feelings to worsen, making it even less likely the parties will resolve their own differences as easily, quickly or cheaply. There is no upside to such nonsense for the purveyors of this.
Contrast that with an occasion in which the opposing side catered lunch for everybody, including us on the other side, during a mediation. It was a nice gesture and created a more positive vibe for negotiations (if you do this, make sure the food is good too)! My message is not, "just buy pizza for the opposing party and you get a better deal," but instead to resist the urge to be impolite and petty. There are enough legitimate issues and bad feelings in litigation without going out of your way to add fuel to the fire, which is exactly what mean-spirited tactics do, boomerang right back in your face. http://www.employmentlawman.com/monday-morning-musings.html