[zacoder]

Time costs money. And you want free time from other people. That little piece of advice you really really need might take a half an hour for an UI designer to write or talk about. And that half an hour can easily be charged to someone else who is willing to pay for it.

It's just supply vs demand. UI/UX design is in very high demand. Every startup and entrepreneur wants a logo, graphic design or a website. Why waste time helping someone out for free when you can charge for it?