When Was I Voted Neighborhood Babysitter?

We spend a lot of time at our neighborhood pool. My girls love the water and it's an easy way to wear them out. There's no lifeguard on duty, so you really need to keep an eye on your children... or not. Every summer I feel as though I 'm one of the only parents who understands swimming pools can be dangerous.
To use the pool without an adult, you need to be 14 or older. Anyone under 14 has to be accompanied by someone 18 or older, meaning a 14 year old can't bring guests. The pool opens at 8am, but the pool monitor doesn't show up until 2pm, and I'm always amazed by the number of families trying to skirt the rules. You can argue that a 14 year old can be responsible for a 10 year old. It doesn't really bother me when a teen under 18 is there with a younger sibling. It does bother me when an 8 or 10 year old shows up with no adult supervision. Basically you're saying either you don't care what happens to your child, or you expect the rest of us to watch your child. What happens when there aren't any other adults there? 
The other day there was a woman at the pool who brought several guests with young children. They let the kids loose while the adults sunbathed. At some point, the adults moved to a different spot so they wouldn't get splashed. A young boy with them, who was two or three, didn't see them move, so once he tired of playing on the pool steps, he had a meltdown, screaming "I can't find my mommy! Where is she? I miss her." Mom's reaction? She never even looked up to see what was going on. I finally went over to him to calm him down and show him where his mom was. The pool monitor came over and took him to mom... and the chewed mom out for not watching her kid. As the woman next to me said "Thank goodness for other moms at the pool."
It's not just the pool where I feel like I'm the only one watching my children and everyone else's. We went to the park last week and a woman showed up with two kids, who appeared to be 4 and 6-ish. She let them out of the car and then walked to the outhouse, which was about a block away. Was I supposed to be watching her girls? This particular park is in a remote area, but there are tons of cars driving by, plus there's a lake nearby. I'm glad I look like a trusting individual, but what exactly do you want me to do if one of them tumbles off the monkey bars? I'm already watching four of my own!
I recently took two of my daughters to a birthday party at Chuck E. Cheese. I was the only parent who stayed with their kids. The other parents camped out at a table with their backs to the game area. Granted, Chuck E. Cheese has a pretty good system in place for making sure children leave with the same adults who brought them, but the idea of my 6 year olds running by themselves wasn't my idea of a safe time. I've seen kids grab other children's tickets, push to the front of the line, etc. Why put your children in that position. Half the games I had to explain to my daughters (and the other party attendees) how to play. We were all having fun, but it was a little overwhelming to be the only visible parent, since all the kids would come to me when they needed help.
I swear I'm not a helicopter mom. I don't hover. At the park, they play while I watch from the bench. At the pool I no longer feel the need to be right at the edge, but I still watch them. I'm not willing to sacrifice my daughters' safety.