At the time when the races were among the entertainment time of families and fans of horse-racing. This practice dates back since the days when the Champ de Mars was converted from a military ground to a race-course round 1812 and in those days everytime the races were organized the Champ de Mars gathered big crowds. During special events, like the Maiden or other important cups, the crowd got even bigger.
This picture from the late 1960s or early 1970s is most probably during the Maiden between Azul, House of Maurice Martin and ridden by Len Hill, and Armed Guard, House of Rene Maingard and ridden by late Jason Espitalier-Noel (information by Irving Henry) and this record attendance claimed over 10% of the population of the island. Judging by the view it looks like the Champ de Mars wasn’t meant to support that much of an audience. But still is shows how in the time a day at the races was a spectacular event, and not only for horse-betting but also as a family event and gathering.
Today the crowd is much less, and reasons certainly include the facilities of the media, allowing people to stay at home and enjoy on their television sets and even bet directly on-line. And also due to the insecurity that prevails nowadays (pick-pockets), it looks to be a wiser choice as such.