Not sure I'd call it "false" but it is a bit misleading. I see this frequently where you can select from a number of pound tests and spool sizes. the advertisement always fronts the lowest price for the lightest line. I have not seen it compared to the highest MSRP spool so there's the mis-lead.
Our local big box stores advertise tires the same way: lowest price in the flyer = the smallest size. By the time I look at the size I need it's 2 - 3 times as much.
That said, if you're fine with some Chinese no-name superline it's still a smokin' deal in any pound test and it does get better the bigger the spool. For example: 80# test and 300 yds. will nick you $18 bucks before S/H (don't know what that is) and for a name brand, best deal, downtown would cost you twice that.
Depends upon what you're using it for and how much confidence you want to have in your line.
