Although it has been explained previously, for some reason you are clearly not up to the job of analysing the interpreting the data, so I'll itemise the issues. If you want you can play at managing a large virtual event and see how quickly with your ideas it degenarates into loss making chaos.
1) A large gala is a multi site event, linked by the trains. It is not a series of isolated independent events, it is one distributed event. Without the dimension of mobility and transport visitor numbers will bunch up at the main location(s), and less people can enjoy the overall experience, they will in consequence stay for less time and they will therefore spend less money on the consumable extras.
2) Offering - or even encouraging - people to buy a heavily discounted "one location only" ticket has a number of tactical issues:
a) it may increase numbers but it also decreases revenue, and the more popular a discounted ticket is, the more people are needed to achieve break even. The more people present, the more uncomfortable and less satisfying it is for those who do attend.
b)If there is one "special visiting attraction" (eg Tornado, etc) any cheap "platform ticket" giving access to one part of the site only will naturally encourage people to visit the special attraction only, thus denying the railway and its exhibitors the chance to promote other attractions up and down the line particularly to those who are not informed enthusiasts. Moreover caterers, shops and exhibitors will all want to cluster close to the special attraction which then has the negative effect of drawing everything back to the centre when the intention is to maximise visitor potential by distributing the event, thus losing overall capacity and duration of stay.
c) the trains are a fixed cost, and without a contribution from every visitor they do not make commercial sense. Yet pradoxically even the platform ticket holder wants to see trains in action. THe Platform ticket idea effectively takes away the ride cost contribution yet the ticket buyer still expects to observe an extended running schedule but from a ficed location rather than being on the train itself.
d) Large events rely on volunteer support and volunteer goodwill. Creating a complex system of travel and non travel tickets tariffs and options makes a hard job impossible, and requires volunteers to become skilled at diffusing inevitable conflicts over the abuse of ticket privileges. Tickets wlll be abused whether intentionally or not, and ticket inspectors on trains cannot check every ticket on every train between every station.
e) A multiple tariff ticket system creates more scope for conflict on a day when conflict is to be avoided. Having one simple overall entry ticket simplifies the volunteer task to an optimal minimum.
f) When facilities do become crowded should a full fare paying family ticket holder be incovenienced by the queues of casual platform ticket holders enjoying the infrastructure but paying a lesser contribution for it?
g) "Platform ticket" tariffs are also going to be used by those who would otherwise have paid full fares and see them as a "bargain" - thus they do not simply cater for an additional extra population of visitors they also encroach into the base visitor population as well, and in doing so undermine the cost modelling of the event as a whole.
g) the production and administration of diferentially priced tickets and tariffs is complex and costly, and difficult to control and plan. When any gala reaches the stage where numbers are going to run into the high thousands they will inevtiably simplify and standardise in order to optimise both enjoymnt and income from the visitor numbers. SMall events and minor galas do not face the same risks and cost pressures and are often at a different level of maturity. WHen they become larger they too will standardise ticket offerings.
You may disagree with this but ask yourself why virtually every large attraction in the country including major railway galas offer a "one price sees all" ticket - and where the only variable attracting any sort of discount is the time of visit and not the scope of visit as you continue to advocate?