I'm not sure how it will work out costing less when you're providing gizmos strapped to kids wrists, specialist airsoft rifles manufactured in the UK and landscaped facilities but let's ignore that part.
Okay, this is my area of work so I'll bite.
What you're describing, though I wouldn't say it's necessarily characterised by an Atlantic divide, is for a company to endure cash burn to achieve economies of scale i.e. operate at a loss whilst deploying to new geographies, capturing new segments of consumers or getting new products/IP to market. To facilitate cash burn you need lenders of capital; large companies use the bond market to raise whilst smaller companies predominantly use private debt, convertible debt or mezzanine financing. My question here is - who is going to lend piles of cash to an airsoft event organiser?
I guess the panel are making the UK/US observation a bit lazily based more on mature markets, which is strange for an angel investing conference; the US's large-cap index can be characterised as tech heavy, where as ours is far more predominantly old world businesses like oil, miners and banks. An airsoft field is not a business model that scales anywhere near as well as what your panel was probably alluding to; tech companies - the increased expenditure required for a tech company to facilitate another 100 million users is negligible; the fixed costs are sunk, the network is there, the data centres, the back end, the front end, the variable costs are basically nill. With an airsoft field, when you reach capacity you have to start another field, i.e. the lions share of your fixed costs double on the spot. All of this is without even addressing the fact the total addressable market for airsoft is what... a couple thousand people in the UK? Maybe double that, even triple? How many of those people are likely to make the pilgrimage to East London regularly enough for you to service your now burgeoning debt from all the cash burn someone has decided to facilitate for you.
I am aware this is all just a flight of fantasy, but still, it's ludicrous to even dream about creating an elite airsoft site with gizmos, squads of near-professional players, private equity/venture capital backers and a magical, infinitely scalable business model.