Selling on Zepto

I'm planning to sell on Zepto, but I'm skeptical on making a profit for the following reasons:

• I heard that Zepto recovers their cost through marketing from sellers. They are least bothered on sales.
• They help only a few top well-known brands in sales. They do not care about new brands.
• They reject inwarding material for weird reasons that results in transportation losses.

People experienced in selling on Zepto - Please adivse.