Probably just that 'Bigger is better!' thing.....like the infatuation with nearly bi-annual manufacturing runs of Big Boys.
Maybe a new trend should be started....sorta like the Nixon-era's 'Ping-Pong Diplomacy' thing: Layouts based on a sheet of 'ping-pong' plywood......2.74 m long and 1.525 m wide, which is about 9 by 5 feet. Larger lumberyards either have them in stock (finish carpenters love them for custom furniture/interior work for their larger size, multiple plies, smooth surface, flatness, stability, etc.) or can special order them. For our great hobby, they graciously allow for larger radius curves in the design of a small layout. And, since storage and play space for ping-pong tables is a fairly common/accepted practice in the home, interior real estate/zoning agents should have little argument against its accommodation.
No, not cheap....by big-box store standards for 4X8 sheets of 'plywood' imported from the Ho Hum Woodworks, Ltd of Wangbang, China. But when the hours of fun and enjoyment will come from a $XXX locomotive...or two...powered by a $YYY whizbang control system, and a few $ZZZ of cars/accessories .......who's pinching pennies at the starting point?.....right?
And, as for the memories of fourbyeight disdain from the Haughty Obnoxious crowd, ...phooey on them!
FWIW, always...
KD