Don't pay attention to the advertisement of the admissions teacher. You go to the training class not because of advertising, but because you have no foundation, so this kind of spending money is inevitable.
You ask those teachers why they don't teach themselves. Not everyone will like the budget, and there will be many exams in the future. It doesn't mean that you will be allowed to do it if you learn it. Experience is the most important thing in this business, but the certificate is the ticket in your hand. Without tickets, you can't do big projects, and you can't find a job with more money. However, as far as I know, people in such training institutions generally do research, just hang their certificates outside to get money, and they don't need them.