Adverts.
 

The people who make the adverts for products seem to think that all of us curlies yearn for straight hair.
They're constantly using curly 'Before' pictures with straight 'After.' and mistaking frizzy hair for curly.
There are heaps of products to turn curly hair straight, but so much fewer to turn straight hair curly.

Lollol!! That's so true and hilariously funny

Yes, been like this for years. It's unfortunate, but it's not unlike any other marketing that pits "ugly" against "beautiful" (in society's eyes)