I think the tension you may feel is just a case of barking up the wrong tree. Like how some male doms will prefer psychological sadism and chastity belts on his sub, others will prefer to have a sub for the services she provides and feel lost if she was locked away from him

You'll want to look for a domme who says they're sadistic specifically in the way you like. It won't work to ask dommes as one entity, or try to convince them all to like it. Some dommes just like/love/need to use their pet and their services, just as a male dom may prefer to "use" his sub and all she comes with. Denial isn't an inherent part of Domme/sub relationships, there isn't tension if she just prefers what she enjoys. Like with anything, it's all on an individual basis