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Join Date: Sep 2009
Location: Minneapolis: DL DM charter 2.3MM
Programs: A3*Gold, SPG Plat, HyattDiamond, MarriottPP, LHW exAccess, ICI, Raffles Amb, NW PE MM, TWA Gold MM
Posts: 102,617
The traditional examples of intrastate flying were TX and CA. In these cases, early LCCs used the "loophole" that such flights weren't subject to federal regulation, including back when CAB set fares.
There are still lots of intrastate flights in these states, although they're also home to some hubs.