Lets try to understand platform fee by thinking about IndiaStudyChannel website.
1. This website has a name called as IndiaStudyChannel and this name is put up somewhere. Think of it as a Birth certificate giving a name to this website.
2. Then this website with the name IndiaStudyChannel needs physical space where all the website coding, articles, videos, photos are put up somewhere. This is called as Physical space , or server or some kind of digital space.
Primarily, money is required for these 2 major kind of services where a name is held for this website and a physical space is needed.
Without these two entities, IndiaStudyChannel website cannot exist.
Now, as IndiaStudyChannel grew over the years, it needed more physical server space to host all of the articles, photos, videos, emails. Also the website name also became more costlier to be held. Thus the platform fee of IndiaStudyChannel increased over the years. Now had the admin of IndiaStudyChannel decided to get this money from its members in return of some physical or digital product purchase, then IndiaStudyChannel could charge a "platform fee" for each transaction that would happen on the website.
What Umesh has mentioned about is if IndiaStudyChannel would had indulged in selling, then it could had charged fees that go to the courier shipping company.
Thus Platform fee - would had been for IndiaStudyChannel to make that particular service available.
Ola, Zomato, Uber and all such portals (also known as platform) charge a fee since they are providing their respective service and they are quite popular and unavoidable. But you can think about them as a way of earning for the particular platform.
Thus if you didn't want to charge a platform fee, you would still be doing so, if you were to sell on other's platform like Amazon or Flipkart.
So, if you consider, any online or offline platform is here to provide a service and is here to earn a profit of their platform, why would they be unfair in earning a platform fee? Infact they are bring honest that they are charging money for their services.
Take an example of an Electrician. If you had some work in your home, you would call the electrician. The Electrician comes , checks your concern, says that he will go and buy the required part and install it for you. When you ask what would be the charges of his services, he says "No, my service cost is covered in the part of the electrical good". Now here is hidden business. As per MRP, the good may be costing 500 Rupees. But when the electrician goes to buy, it may cost him only 150 Rupees and he earns 350 Rupees for the service. Even worse, he might simply buy a dirt cheap good which may cost him only 50 Rupees and you do not realize that you have been charged 450 Rupees by the electrician to fit that Rs 50 product.
Let us take an example of Google AdSense Revenue Sharing program. You write an article for IndiaStudyChannel and the website offers 90% revenue share for the article for 1 year. After 1 year, IndiaStudyChannel continuously earns 100% from your article. You are happy because you did not require to invest in building a website. But IndiaStudyChannel kept on earning for your write up over the next 20 years from your article. While IndiaStudyChannel did pure business relations with you, you actually did not know the real value of your write up.
But here the business proposal is hidden from you and it may seem very well that IndiaStudyChannel duped you in the long run. This is because we saw short term gain that we did not need to make any website.
Here instead, if IndiaStudyChannel would had offered an annual platform fees to keep the revenue sharing ongoing, it would had been a fair deal on part of IndiaStudyChannel to keep on earning money from its members. And for those who now did not want to pay for the continued revenue sharing, they could now have claimed complete ownership of the article and not receive the platform fee.
Thus, when you do not know what is platform fee, it is incorrect to call upon and out rightly say that charging platform fee is unjust.
