Hoffy,
If others say the WiFi sucks, then take that to be an understatement...
For many years now, campground WiFi systems have been both poorly implemented (the regular case with older) and overloaded (the case with most).
If you really need internet, your only hope is to bring your own in the form of either satellite ($$$-latency problems) or a cell signal hotspot (as mentioned above). If the campground is remote, a repeater or booster may be needed. Depending on where you are in the country, sometimes even that is just not enough.
Oh yeah, the carrier counts for a lot too. Do not believe the "We use XXX towers" line, I will not take the time to tell why here and now.
Good Luck.
Matt