I’ve thought about this from time to time. As a sub, it is a bit odd to me to put trust in someone who I typically know very little about, including not even their real name. Conversely though, it’s hard not to quickly build trust with someone when you are letting them tie you naked to a chair, bench, cross. Being completely at someone’s mercy tends to build trust quick. I think for many of us who lead pretty vanilla lives, our only outlet for any bdsm urges tends to be pro Dommes, so putting trust in a stranger is required.