Who wants to bet that the spelling errors were in the original DOT contract award document?
I sort of doubt it. Not that I don’t think DOT has staff perfectly capable of that (and obviously DOT employees went right ahead and installed the sign). However, if the order arrived like that from DOT, somebody at the place that made the signs would presumably have caught the misspelling of “business”. With place names, somebody who isn’t familiar with the area can’t be expected to know whether or not a place really does have an odd-looking spelling. But “business” is spelled the same way everywhere, even in the UK. This also could have been the deliberate work of a disgruntled employee at the sign-maker.