Okay, I'll bite.
NOT secret and hidden? Okay, agreed, not entirely - but I'd suggest that said information is not as clear as you might be suggesting. The below attached is what your kid or spouse managed to dig up on their tiny computer (assuming you're not traveling on your own, AND that they can find it). And that the website is functioning properly (cause it doesn't always do that, check out the "toll rate example image" on the page, example attached)
Except signs give the tolls for one segment of the highway - not the whole length - only for the smallest vehicles, and make no signage provision other than showing the base rate and saying "Larger vehicles pay more." (example sign attached, as well)
So, make an economic decision at 60 mph, piloting 18 tons of Class A or dragging a trailer. How much is your toll going to be?
The point is that the information needed to make a good decision - even the basic information of what the economic exchange is going to be - is, kindly, obscured and definitely separated from other necessary information required for the calculation.
Driver: "How much will using this toll lane cost me?"
Toll system website (NOT a road sign, mind you): "Here's a rate sheet, divorced from the base information you need in order to know what the terms are. Also, there's another complication about a peak tool factor. Figure it out."
For RV drivers unfamiliar with the area and/or new to the concept of a toll lane (of which the story seems to be about, and likely describes many RVers on a road trip), this particular toll system seems to (1) needlessly obscure the relevant information that an individual requires to be able to figure their toll and (2) be needlessly complicated.
In terms of mobile usability, I give the pricing page a FAIL. How about a calculator baked into that sheet that lets a person plug in their details (or even just identify and select their toll class) and a distance (start and stop of the toll lane) to calculate out their toll AHEAD of time? How about a baked-in clock that says whether peak rates are applied right now or not? None of this is rocket science and super easy to apply (esp if you've got RV'ers paying $600(!) to run the length of the toll lane).
In terms of system design, I'll give the pricing structure a C-. Needlessly complicated by breaking the users into too many different categories, potentially based on "wear and tear?" (eg, "a motorcycle is negligible, but a Class A, bus or semi is going to wear our toll road at a rate up to 8 times of a full sized SUV or commercial truck"). If it's about recouping expenditure, easing the burden on all motorists, and reducing the amount of post-service support (like chasing down $600 worth of tolls on a single RV'er), then reduce the number of classes to 3 instantly recognizable/sortable ones (like small/medium/large) and POST THE ACTUAL, AT TIME COST for each RV on signage legible and understandable to the driver (with no math necessary).
But now that we've touched on it, perhaps there's something ELSE at work here. I'd suggest that the toll structure is (perhaps needlessly) complicated and (somewhat) punitive - ultimately designed to keep anything but Toll Classes 1 - 3 OUT of the toll lane in order to keep the toll lane advantaged over the rest of the road (which makes a lot more sense). Now there's an impetus (at least for classes 1-3) to use the toll lane, keeping revenue up.
Traveling by road is already complicated, and yet should be as simple and easy as possible. Couple that with more distractions to drivers AND the challenge of towing (cause say what you will, but dragging an RV or driving a Class A is not as easy as driving, say, a SUV) and I'd suggest that this isn't a good or as optimized system as it could be.
Just my .02, and food for thought. Your mileage may - and likely does - vary.
