Somethings the price varies on size while other items it does not.
Eg clothing prices mostly are the same for small to extra extra large.
SUPs 8ft is same as 11ft, similar for surfboards same price all sizes.
Seats on a plane- price for a 50kg person is the same as 100kg person but the 50kg person may pay more for excess baggage, why not get an extra 50kg for bagage at no extra cost to offset the 100kg person.
But foil masts, kites, beds, and more the price increases relative to size..
Please explain.

I guess it depends on the ratio of material costs to labour costs. Quite often the amount of labour involved doesn't change much with size, and if material costs are low, then there won't be much price difference.

Mastbender said..
Demand is one if the main reasons for pricing strategies, which can defy all other logical reasons.

Clothing and shoes have the same price regardless of size is probably because (1). Materials cost much less in comparison to labour cost, and (2). Smaller sizes probably subsidize bigger ones.

Air travel is another strange one. Would females be paying less because they are "statistically" lighter than males. With people getting more and more obese, I think airlines will need to have bigger engines and/or lower cargo weight to compensate. I know Tonga is having to deal with such an "organic" problem right now. Do you know that Tonga has a "growing" problem of obese amigos ? Yes, they are getting bigger, side-way. I believe the national carrier is imposing a "fat tax"

Jupiter said.
shoes have the same price regardless of size is probably because (1). Materials cost much less in comparison to labour cost, and (2). Smaller sizes probably subsidize bigger ones.

100% incorrect.

My personal experience is that the majority of shoes i buy i pay about $20 more, if they even do that style in a bigger shoe.

Steel Blue are a perfect example. Local company and do 3 dozens styles of shoes right? In my size (16) they do 2 styles. The Hobart and Argyle and i'm then charged another $30 on top of their normal price.

Unfortunately we cant buy shoes based on style, colour or price. I just walk into a shop and if they happen to have anything in size 16 i have to buy it. Unless its in the US, they don't discrimate against big feet