I can remember those (just about) as a kid; recall hearing people say things like "We must be near a town - there are the Burma Shave signs".

We can easily give this thread a musical element by citing Tom Waits' brilliant Burma Shave song (loads of clips of it on YouTube). I love the slightly surreal twist of Burma Shave being perceived as an actual place, some Neverland of the mind, always just beyond the horizon.