So what does the recruiter mean by saying that?
The recruiter means that they intend to maintain a relationship with you by giving you a phone call or e-mail in a few months to see where you are. Perhaps at that time you could want to explore opportunities or require their services to fill a position where you currently work that could be a win-win.
If they don't want people now why did they bother scheduling the
They want to know how to categorize you amongst all the other people that they have on file. Are you an intermediate developer with technologies X, Y and Z? Are you wanting to be a manager or an architect next? These are questions that only get answered by asking them directly after reading the resume.
And if no technical topics were covered, how did they know the
candidate doesn't fit the position they have in mind?
Be careful about what you assume happens in these interviews. If they are asking the questions to see if you are going into a manager, developer, tester buckets then what you see as general is actually technical for them. You don't know what were the key things they wanted to know. They have their database with a # of contacts or which Y are skilled with Z years of experience that can be useful for the firm to mention to possible clients. I'd likely wonder if you could see the bigger picture here or even the recruitment firm's perspective to some degree here.