Hi (thanks for the welcome. Long time listener first time caller and all that!). Tbh, your experience is symptomatic of many places in the industry. The consultants know next to nothing about the tech industry, cant tell their C from their C++ and think Ruby gems are literally precious stones. As for your point about not recognising seniority levels, I can't begin to tell you how many times this has come up in conversation, especially with my manager. It is keyword/buzzword recruitment at its finest. If the words on the job spec don't match the words on your CV, most people will just disregard it.
I'm on a literal quest to try and get people in my company to be able to at least recognise code on Github, or recognise the importance of things like Stack Overflow, but they don't want to. The harsh point is that really good technically able people who would suit a role we come across won't be on the job boards, or have their CV registered with us. They'll be on online communities like these, or at tech meetups etc. A lot of the CV's we get through aren't the sort of CV's that our clients want to see. Hell, they don't even want to see a CV. They want to see code samples, HN profiles etc. But it's an uphill battle for me.
I think that if consultants DID do this, they'd be a lot more reputable and respected in the market. As it is, more focus is put on speed rather than quality/customer service unfortunately.
If I were you, if you don't think they'll represent you properly, I'd cut and run, and make a point of NOT recommending them on further. Anything you say in complaint will most likely be ignored. Just ensure that they're not putting you in front of companies you might actually like to work for, as they obviously won't be doing a very good job.