There has been some places that is doing this but the most recent and huge one is binance. The problem is that you are not making too much money so people do not see it as a way of making money.
Everyone thinks that when you give people 3% or less they would see it as an investment or some sort of savings account type of thing you make money but in the end there are many many poor countries in the world with higher than 3% interest rate already, even freebitcoin as a company gives 4% bitcoin return and why would I pick an inferior bad altcoin that gives me 3% or even 4 when I could just pick the OG coin bitcoin with 4% interest rate? So, only time it will actually get more popular will be when people actually have coins that gives them 10% or more which would make sense to invest into.
Thank you el kaka22. I know about Binance but I prefer working with a Swiss exchange rather than a Chinese. Why do you say you can not make too much money? SMART VALOR gives up to 6.9% which is a lot especially since I see it as an alternative for interest which is equals to 0 or even negative here in Switzerland. Even 4% would be fine for me since I am in crypto for the long term.