What an interesting topic.
This is one of those proverbial double edged swords. Let's see . . . if we do not vet people, we run the risk of what? Wasting their time as well as ours. We also loose the opportunity to go with the flow and see what happens. If we vet people, then, well, it can now look like an application.
Our take is that . . . we will always vet. We don't see it as being an asshole to the other party(ies), but actually being courteous. We are forthright in what our agenda is, what our expectations are, what our boundaries are. As we do not know the other party(ies), we are completely unaware of what their agenda is, what their expectations are, what their boundaries are. If we are at least explicit in what our agenda is, then the other party can determine if they are in alignment with it. If not, then we can either 'negotiate' until we can come to an agreement or we can determine there is not alignment and move on.
It was interesting reading CA's profile. I appreciated the candor in it. I am not a SM, but if I were and was interested in them, my approach would be simple, "I read in your profile you have allergies to fragrances. I use . . . Is this ok, or would you want something else?" What they did was a form of vetting and I appreciate that. Why? Because if I didn't know that, showed up wearing a bottle of Drakkar, I would have not only ruined their night, but mine as well.
Now, you can argue as much as you want about the depth of the hoops to be vetted. That is a different subject. But when I read through the OP, I am reminded that some people feel this is McDonalds. They can go up to the counter and say, "I'll have a number 4." and suddenly it is delivered to them, on a tray, in 45 seconds. They tend to forget that the product that they are ordering is actually another human. That human has an agenda, just like yours. To expect them to be on call, subservient to your demands, is just fucking immature.