I think it's nuanced. We aren't relationship substitutes precisely because we create an experience for the client and yes that involves different types of intimacy and companionship.. we do offer things you can get in a relationship but ultimately if a client starts seeing escorts because he wants to turn one of us into his real girlfriend he's going to be disappointed.
I see what I offer as an escort as something "in between".. I care about my clients and I want to offer a good experience, but I'm not their girlfriend. To me what I offer as an escort is a bridge to a real relationship with someone else really often. It's also yes entertainment. Really often clients book me because they want to be around an interesting and intelligent girl who they can also have sex with and do things you'd normally do on a date with.
I also disagree. A lot of client who hire escorts purely for sex tell themselves and each other stories too..