I would be quite delighted if I saw a house in Worcester which had a 'Please remove your shoes' sign on its door.
Personally, I think this is not the most polite way to ensure shoes-off, but I would still be very pleased to see a house with such a sign. I would feel that there was somebody of like-mind in this desolate city of Worcester (the English version, not the one in the Massachusetts).
I think if I saw a house with such a sign, I would probably drop a letter of appreciation through their letter-box; just to encourage them in their courageous stand.