A consumer grade GPS can have an error like that 30ft, my new verizon phone has a gps and shows the error circle just like my garmin when I zoom in far.
High end GPS's are use to make the roads, the surveyor grade stuff is both very accurate and expensive, I've seen farming applications where the gps keeps the crop rows straight and tags where every seed is dropped.
I seem to recall a similar thing happening last year even. truck drivers were talking about it saying it wasn't a big deal for them with 50-100 gallons of fuel and a sleeper on the back of the cab with their bed, food, etc, they could stay for days.