Passage Summary: Even though new giant planes have room for cool stuff like shops, they'll likely just be filled with more seats because so many more people will be flying in the future.

Conclusion: The extra space in the new, massive passenger planes will probably be used for more seating rather than for amenities like shops or lounges.

Reasoning: Air travel demand is expected to triple soon, and current airports won't be able to handle enough standard-sized planes to meet that capacity.

Analysis: The conclusion is found in the second sentence, signaled by the contrast word 'However.' The author acknowledges a possibility (shops and lounges) but then pivots to their actual claim about seating. The final sentence provides the evidence regarding air-traffic growth, which explains why the author believes the seating prediction is more likely. When identifying a conclusion, always look for the statement that is supported by other sentences rather than the one doing the supporting.