Comment by petesergeant

Source: I've been a programmer for 25 years, and ran a recruitment company for 8.

This happens, but it's unusual. It's normally only really something you'd bother with as a recruiter if you were doing CV marketing, that is, reaching out to people who aren't your clients saying "this is the kind of person I could get you!". They're not really meant to do it, but recruitment regulations aren't strongly enforced in most of the Anglosphere.

To fill a role with one of your clients, they've signed T&Cs that mean they can't really cut you out, and assuming they don't hate you they also don't want to lose you as a recruiter. Fucking candidates absolutely will try and occasionally cut you out of the process -- usually out of incorrectly thinking it will help them land the job because the employer won't have to pay a commission.

There are many shitty recruiters, but finding a good one will absolutely help you find good roles, and can do all sorts of useful things like make sure you're asking for enough money, get feedback that you wouldn't directly get as a candidate, harass the hiring manager about your application on your behalf, and engage in a dialogue with the hiring manager about your application that virtually no hiring manager would be willing to do directly with you.