Kicking them doesn't help you at all on a freemium token site. They could as well open your room as anonymous user or use hidden mode on SC.
The only thing you reach by blocking/kicking them is a a brief feeling of satisfaction, when in reality you hurt yourself by loosing users that are potential future customers (much more than any grey user) and on some sites help you push the ranking of your room.
There are many different types of users. Some take longer to get to a point where they spend their money on a model, others don't do it at all in public chat and therefore only observe if they can imagine a PVT session with you, others open 20 browser tabs and are not really watching your stream. There are many reasons for such behavior and none of them really speaks for becoming active in the form of a kick/ban.
Every minute that such a user actively observes you (if he is in your room for hours, he probably doesn't do that most of the time) increases the chance that an action of yours makes him click and he decides to tip you or to make a PVT request.
And even if they never tip, they were nothing more than a slightly more noticeable grey user who will at some point move on when they get bored of passive consumption but couldn't be convinced to "buy".
Just accept them as part of the deal on a token based site or move to sites with other business models. Anything else will only hurt yourself - financially and/or mentally. Kicking doesn't solve that constant negative feeling - if you don't learn to accept freeloaders of any color, it will only get worse over time, because you can't kick 90% of your room. You're just wasting time and energy and attention that you should be putting into paying customers.
