Is it a good idea to pay users crypto tokens as rewards for their activities?

The idea is to make a website where users can share their experiences (write reviews) about products, movies, etc. As an additional motivation factor, it would be great to reward users by paying them for their reviews, moderation, and so on. At the same time, brand owners might pay for their membership—the particular "economics" to be discussed, this is just an illustration.

It looks to me, that, in 2023, we can use blockchain for that, for example, to create a token based on Ethereum. My questions are:

1. Do you know who is doing such a thing? Are any existing services/websites?
2. Is it legal?
3. What is better (or what is right): create a token or use directly one of the cryptocurrencies?