As a new author, it can seem frustrating. But I find these terms to be completely fair.
1. These are some of the best rates in the industry. Envato has overhead, and they provide a big service. They handle payment gateways, provide server bandwidth, host your files, provide server maintenance and uptime, handle advertising, and most importantly: offer a ready-made customer base. Files here get way more exposure than you could hope to have on your own site without spending huge amounts of time on advertising. While it’s disheartening to share part of your profits, you need to understand where that’s going; Envato earns their cut.
Also, they offer an affiliate program, which receives 30% of the purchase. This has 2 implications: (1) when an affiliate sale is made, Envato may earn $0 and (2) once you reach 70%, you have the opportunity to essentially earn 100% commission on sales you refer from your site.
2. This keeps the marketplace’s value high by ensuring uniqueness. Without this rule we would all suffer, potentially leading to a price war with other marketplaces and devaluing our products. However, if you find it oppressive, you can opt to be a “non-exclusive” author and sell your files elsewhere without restriction.
In the end, you have to go where you feel comfortable. If you feel oppressed by these rules, you can always start your own theme shop 
Request processing...