I recall seeing Cubs doing banner towing along the beach at Miami/Fort Lauderdale, several seemed to be labouring along in a fairly nose high attitude.
Many years ago we were treated to the sight of a 172 hauling a large banner around Croydon town centre. From our office on the 18th or 19th floor, the aircraft appeared to be not much higher than we were - I'd say 500' was optimistic. Can't believe it was legal.