My Husband, who is from NJ states they called it Mischief Night and confirms that eggs and shaving cream were not sold that day or sometimes the day before as well. They did it on Oct 30th.

I grew up in New York where that kind of thing was severely frowned upon. In fact, my local school district claimed Oct. 30th for safe trick or treating for smaller children and hosted a Costume contest for grade-schoolers. This went on through the early 1970s. Opprtunistic kids from the district then went and visited cousins and friends in other districts for oct 31st so they could squeeze in a second night of trick or treating. My parents would never let us do that.