I think the concept has legs. Perhaps my understanding of the concept is a bit off, but I understood it as a type of "event" business. My 'day job' is as a strategic food retail consultant. And I can tell you that 'event' type businesses are doing very well. Especially as a result of covid.

It is better to have some food knowledge, but not essential - and the money is in the merchandising and product placement. If you look at American-style BBQ or spit roast operations (similar), they sell sauces and condiments, t-shirts, etc. And it is big business (and added marketing).

If you make a dough starter (unique) and market it as such with a 'homemade' pizza sauce which is saleable ... and topping spice blend, it can be franchised as well.

To make this work it has to be a one-stop all in operation. If the customer has to do work, it will not happen. They must call up, order for x-number of people, and be done with the food side of things.

One downside to Scotland is the weather. But it is not insurmountable - just extra expense - marquee of covering, is essential.

Ultimately it is a logistics business though and capital intensive. you will need several ovens and setups to make it a success. But it is easy to trial and then scale up if profitable.

If you want input, I would gladly do a proper note on it for you as a favour. for payment, you just have to put a cone on a statue for me ... lol