You are certainly right about urban campgrounds. It is much more feasible to wire them up with higher capacity solutions. However there are still some roadblocks to overcome. When calculating your bandwidth budget, you start with your worst case scenario, lets say 7pm, assume 2mbps per campsite (enough to do one Netflix stream or one low bandwidth Youtube) despite there may be multiple devices per site (the average these days is about 2-3 devices per person, so a family of 4 could be as many as 12 devices (not likely but possible). Then multiply the 2mbps per site by the number of sites, say 100, that makes 200mbps. Any good network engineer would then add 40% for unknown, just in case, and what if. That gets you to about 280mbps. Now if we look at the options a campground could have access to in an urban environment:
T1 1.54mbps
DSL abt 25mbps max
Cable abt 100mbps max
FIOS (not sure, we don't have in Canada so I won't comment on it)
Fiber basically anything you want up to about 10gbps if infrastructure supports it
You can then bond multiple connections of the same type with expensive specialty hardware and if your ISP supports it. You could theoretically cover the bandwidth budget above with 3 bonded 100mbps Cable feeds at 3 times the cost per month plus the hardware. This could possibly give a working solution for under $500 per month.
You could also do it with Fiber at several thousand dollars per month but only if there is Telco Transport fiber on the street out front and you are willing for them to run a conduit from the pole to your building ($10,000 or more). If no Telco fiber is near by you could be looking at hundreds of thousands to millions of dollars to get it run to you.
I have not included any over the air or line of sight solutions in my scenario as they are typically just too unstable for long distance, high bandwidth, multiple users (like dozens or hundreds of Netflix users). I have run WIFI many miles and it will work OK under low load, but as soon as the Netflix starts your error rate will skyrocket, and in the fall when the leaves drop, or during a storm, there goes your bandwidth. Unfortunately there is a reason the worlds backbone and most large organizations are built almost exclusively on Fiber optic cable. I am not aware of any over the air solution that is capable of delivering remotely close to the bandwidth required, is stable under load and stable under adverse conditions like weather. Fiber optic is the only solution that is capable of delivering high bandwidth over any long distance with virtually no errors.
My personal opinion is free WiFi at hotels and campgrounds is a thing of the past, it is simply not sustainable. It is just too expensive for them to deliver the needed bandwidth to do things like Netflix. I think in a few years we will be seeing free unrestricted WIFI disappear and different models like pay to surf daily rate like some hotels and campgrounds already do, pay per MB, filtered access (blocking media rich services like Netflix and Youtube will be the way of the future. I no longer expect anything useful from "free" WiFi anymore and rely on a hotspot, but would be willing to pay for some guarantee that I would get usable bandwidth at a campground especially if it was cheaper than my hotspot plan.