Most courses use man made ponds as both hazards and as retention ponds so they can use that rain water.
You know what uses three times the amount of water per acre? Corn. And almonds use about ten times more water than corn. And people have only just started caring about lawns, that use two orders of magnitude more water, fertilizer, and land than golf courses.
Golf courses really aren’t that bad from an ecological point of view when compared acre per acre to other large man made structures. They’re generally pretty small when compared to other large landscaping projects at 30-80 acres. The issue is when a city has like twenty courses just for the purpose of driving up housing prices.
Would that land be better as a park? Probably, but this is the US, someone would see an unprofitable “empty” plot of land and throw million dollar houses on it.
Most of the US corn crop goes to animal feed, so no you don’t get food from it. At least not directly. If you totaled up all of the land used by golf courses, you’d be at .1% of just the amount of land used for animal feed. And about 1% of the land used by home lawns.
They’re not that bad, there are much worse enemies than golf courses in general. Again, courses that are in the middle of a city that do nothing but increase property value are terrible, but most are perfectly fine and use way less water than you think.