In order to better provide for the public welfare, safety, comfort, and convenience of their inhabitants, incorporated towns may alter or change the width or extension of streets, sidewalks, alleys, avenues, parks, wharves, and other public grounds, and vacate or lease out such portions thereof as may not for the time being be required for corporation purposes, and, where lands have been acquired or donated to the town for any object or purpose which has become impossible or impracticable to achieve, the lands may be used or devoted for other proper public or corporate purposes or sold by order of the town council and the proceeds applied for public or corporate purposes.