Sparks Group interview questions

Interviewed for a job that I applied to on LinkedIn unaware that it was a placement agency as no content on the JD indicated as such. Furthermore, was told quite quickly that my pay expectations were out of alignment for the position (please PLEASE include pay ranges!!!) but the interview continued. When I asked why there were additional questions that interviewer said they were going to keep me in their system. This was when I was made aware they were a placement company interviewing on behalf of another organization. It just felt weird. Would have appreciated more transparency.