I think you have to weigh up the cost of studying a program (both financially and in terms of the investment of time) against your objectives and the benefit that the course will bring you. I think this applies to any training program.
If, for example, you are planning on teaching for only a year, then a one year training program costing 40K is probably not a viable investment of time and money. If, however, you plan to make teaching your career, then maybe it is.
A 4 week course costing 2K rather than 40K is often a more realistic option in this profession. Courses such as the CELTA are excellent introductory programs, designed to give you the theoretical and practical basis to start teaching, and recognising that your learning will continue when you start to teach.