why not use rest proxy of confluent io directly?

this is an interesting repo, but I have one question. 
Why not use the restful proxy provided by confluent.io? it has the features of registering schemas, serializing and deserializing data using avro, json, etc. Besides, it has the build in feature of talking to kafka. Actually, one only needs to post and get something. What are the prods to use this instead of the production one? 
