I know where you heard it. During the DC Beltway sniper stuff in the late 2000s, the first few months of coverage and press suggested that the suspects were sniping from a white contractor type van. Everyone started paying attention to white vans, and reports of white van sightings became universal damn near everywhere. Turns out that white vans are ubiquitous and functionally invisible. You might want to think about why that might be the case. Oh, and the DC sniper turned out to be using the trunk of a sedan, not a van.
All kind of bad shit is done using, or from, or out of, or inside of, white vans. You literally take no notice of them. Tomorrow, drive around and count the white vans that you see - church vans, utility vans, school vans, landscapers etc. etc. it never ends.You could run a functioning meth lab on the DC Mall in the back of a white 17 passenger van with tinted windows and a Korean Baptist sticker on the side.
And don't even get me started on the fact that one can trespass just about anywhere with an orange vest, a white hardhat, an aluminum clipboard, and a sufficiently vague "clearance letter"
Yes, why is it when some dude snaps and goes on a killing bender, the stock line is "he was real quiet", or "he seemed like a normal guy", or "he kept to himself"? Why are the neighbors never like: "yep. I knew he was makin' skinsuits up in there. Screamin' at all hours of the night. Shit, blood be dripping out of the trashcans,' Why is that?