Power to require removal of any structure or fixture erected or setup before the appointed day.

The Commissioner may, by written notice, require the owner or occupier of any premises contiguous to, or in front of, or in conection with which any wall, fence, rail, post, step, booth or other structure or fixture, which it would be unlawful to erect or set up under this Act, has been erected or set up before the appointed day, to remove the said wall, fence, rail, post, step, stall or other structure or thing: Provided that, if in any such case the structure or fixture shall have been lawfully erected or set up, compensation shall be paid by the Commissioner to every person who sustains loss or damage by the removal or alteration thereof.