1. It established harmless rules and regulations about the use of the properties. Basically, you can't keep junk cars on your front lawn, you can't park commercial vehicles in the street, and you can only park RVs on the street for 48 hours at a time.
2. The subdivision backs onto a creek and has a large landscaped area in the rear for stormwater detention. The HOA is responsible for maintaining this area and paying the property taxes on it.
There was a movement among several owners last year to disband the HOA. That would be an enormous mistake, and I have no idea why they wanted to do it. It only costs each homeowner $75/year in HOA fees.
The next subdivision does NOT have an HOA, and whenever a home comes up for sale there the listing includes a prominent boast that they have no HOA. I looked at a home over there before I bought this one. The neighborhood is awful, and looks like a rural slum with all kinds of trailers parked in the street and cars and junk all over the lawns. A home over there typically sells for about 40% less than a comparable home in this subdivision.
Sounds like the presence or absence of a HOA can be a selling point or deal breaker for different parties.