Absolutely intimate dating sites
They may be sold to a different owner who uses different standards or may engage in some of those shady practices to boost membership and use. My first recommendation would be to try Lavalife's Intimate Encounters section; you sign up with them and then decide which of the three sections you want to be a part of (Dating, Relationships or Intimate Encounters).
You can use different handles in each section under the same account too, so no one will be any wiser if you want to advertise for one thing in one place without ruining your chances for something more should it come up.
We’ve found the nine top free online dating sites that don’t skimp on the experience.
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It's pretty hard for any site these days (especially the big ones) to stop fake profiles and scammers from signing up, but I think I get what you're after.
There are a lot of adult dating sites that don't have a lot of users, or use sneaky marketing tactics like the bait and switch you're referring to.
After Lavalife, I only know of a few others that are worth mentioning, although I've yet to find one that's truly ideal.