Seam seems to generate interceptor for all methods on a bean, even on protected and private methods. I think this is not neccessary. I once saw a long invocation stack with many Seam interceptor methods in the middle. I think this may hurt performance and make debugging harder. At least, there should be some options to exclude certain methods from being intercepted.
Method-level interceptors are a planned future enhancement, but I'm not sure that this will really solve the problem.
This is definitely a (minor) drawback of EJB3 interceptors which must be around-style interceptors. Bill Burke designed the EJB3 interceptors stuff, so I had better not sound too critical or he will yell at me :-)