[beeflet]

I have been thinking of a device to thwart license plate readers by dumping a ton of IR and/or visible light on the plate before it gets read.

Perhaps combined with some reflective coating? Retroreflectors are promising

[delis-thumbs-7e]

Repo men use those readers to track cars to be repossessed. And as it happens, it is very successful industry these days.

[fwip]

Just as a heads up, this is likely illegal in many US states. (Legality is not morality - but it's good to know what the law is before you might break it).