My experience with employment agencies has been mostly positive. Positive more often than not.
I've never gotten a job by filling out a job application. Most of my work experience has been through employment agencies. Most agencies seem to place people for temporary, temporary-to-hire, or permanent jobs.
I think many people use employment agencies wrong, or they are just repeating what some guy who had a bad experience with job agencies said.
Here's the deal. There are many employment agencies. They list the industries they fill on their website (retail, warehouse, office, administrative, etc). They show on their website if they fill temporary, temporary-to-hire, or permanent jobs.
If you're having a bad experience with job agencies... you must've applied to one that doesn't match your needs, or you don't apply to enough job agencies. In theory, if you apply to several agencies that match your needs, they should be able to get you work. That's just common sense. If an agency isn't giving you work, then something must fundamentally be wrong.
I don't get why job agencies are so hated. Like I said, my experience has been positive. Employment agencies actually give you work, unlike sending resumes online. Why do people say they hate agencies? Employment agencies are the best way to get a job.