I never attach my garden hose to my camper and campground spigot. One KOA we stayed at a few years ago told me their water pressure was 120 pounds, to be sure I used a pressure regulator. It was at that moment I decided to fill my fresh water tank and run exclusively off my on board water pump. I've been doing that ever since. So, high pressure, low pressure, or no water at all on the actual site, it doesn't matter!
About WIFI? We've been in only a couple campgrounds in the last 10 years of camping that had WIFI that actually amounted to anything. So, we never depend on campground WIFI. We use our phone hot-spots. Never a problem. And really don't care if the campgrounds advertise WIFI or not!
About concrete pads? What makes the difference? As long as you are level and dry, what should it matter. KOA's are not 5 star RV Resorts! I've never had a concrete spot at any KOA in the last 40 years of camping, from tents to trailers.
What IS important about KOA's is their convenient location. Most are located right along an Interstate which provides an easy in and easy out, easy access from the Interstate with out having to drive out of your way. They are convenient, always clean, and absolutely great for just an over-night. 99% of the time we are at a KOA, we don't even unhitch. For the convenience of having them right on our route, ... well.... $47 is worth it!
And we've never been to a KOA that did not have full hook-ups.
What's the alternative for the OP? Maybe he should spend the night in a motel!