Oops, upside my head

This dry cleaner's store has had this special offer sign in it's window from, at least, last week.
Now the question is this; was it deliberate as an unusal marketing ploy that people will notice ? Or was it an accident that the public have not went in and pointed out to them, thinking hat they probably already know ? Or are they just far too lazy to take down ? By now they surely must know, so why have they just left it ? What would their head office think ?
Because a young London couple were getting married today the Aberdeen night clubs were alowed to stay open until 4 a.m. as opposed to closing at 3 a.m.
Go figure.