Recruiters, especially those who work for third-party recruiting firms, are sales people. They have a series of incentives that only loosely align with "find good candidates" and almost never align with "don't piss off said candidates." There are some very good recruiters out there, most seem to be employed directly by the company they're recruiting for, but the rest of the lot might as well be in low-end used car sales.

If they set up an interview that you didn't request, that you don't want, and you go to it - you're the one to blame. Chances are you contributed to part of their incentive pay by participating in that interview. Further, they're not 'taking "no" for an answer' because you're not telling them "no."