I agree. You can take two brands of line, both 6 lb test, and one is going to break eaiser than the other. I've seen it all my life.
And no doubt the smaller packaging is going to mean higher costs. But I just keep visualizing the line coming off a machine somewhere, and the same line goes onto both fishing line spools and then on tippet spools. Only difference is the tippet is 10 times higher in price. I've got some great brand name FC line that comes in 200 yd spools that is .001" larger than my 6X tippet. Much, much less expensive per foot. I can't believe the fish can see this one thousandth of an inch unless it's under very unusual circumstances.
I won't beat this to death, just wondering and would be interested in other opinions.
Jerry