1) Kitchens with single sinks
Is there anything more infuriating than trying to wash dishes in a single-sink? And there's no way that using a single sink dishwashing is less efficient in the long run. Simply put, a requirement for at least a double sink should be in all building codes (and retrofits required for those kitchens not in compliance).
2) The wearing of three piece suits in the summer
I get it that all kinds of guys with three piece suits don't have that many opportunities to wear them, but that doesn't mean it's OK to wear them when it's 30 degrees outside (just think about all of the AC costs). A further benefit is that this ban will prevent those who might be inclined to wear a three-piece suit in the summer from looking like doofuses. Everybody wins with this one.
3) Tomatoes
Just because they're the grossest. Yuck.