One day last year, I spent absolutely nothing. Nada. Zero. Zip. Season passes for both myself and my car covered all admission costs, and a cooler filled with subs, Cokes, and chips took care of the rest. The urge was great, but I resisted playing Fascination, too (since I don't like playing when there are more than 30 people). A round-trip took about 3/4 of a tank, or around $9, if you want to include that.
However, this was, as many of my trips are now that I've had season passes for the past few years, only a half-day trip--arriving around 2 PM and staying to maybe 10 or so. On full-day trips, I will end up spending at least $15 in the park itself (which I don't mind spending all that much since the season pass will have gotten me in "for free" (as it were)).
The most? Over $600 in a single day--BUT this included all kinds of season passes for the next year for myself and various family members who couldn't come out and buy their own, as well as one of the videos to tide me through the winter, a copy of "CP : the queen of American Watering Places", and a Christmas present or two (or three), and all food and drinks (since I was entirely too lazy to go out the night before and buy the subs like I usually do).
John
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"Thank you for riding [fill in name of ride], and enjoy the rest of your day here at [fill in name of park]."