LaSalle Network interview questions

i had saw a job posting and applied online without realizing LaSalle is a recruiting agency. Not a big deal, figured I'd see what came of it. Recruiter reached out to me very promptly, and wanted to set up an interview. The interview started off very high level about my interests. What really put me off was that the interviewer kept probing me about why I had decided to leave my last employment (various of personal reasons I felt I shouldn't have to go into details). Then she asked me to talk about my past experience. I assumed the recruiter would be familiar with what I had worked on, as the position is in similar background as my previous job. It became apparent pretty quickly that she was hiring for a job whose role she knew little about. At the end of the interview, she tells me the job was looking for someone with about 5 more years of experience than I had and that my available start date wouldn't work for the job. Okay, so why did you interview me? Please don't waste people's time with interviews when you already have all the info on whether or not their background or timeline would work for a job She told me she'd be in touch with any future opportunities but I just politely declined