Others can also plug in to have the experiences they want, so there's no need to stay unplugged to serve them. Nor should you refrain because of the few moments of distress between the moment you've decided and the moment you're plugged. First, we want to do certain things, and not just have the experience of doing them. In the case of certain experiences, it is only because first we want to do the actions that we want the experiences of doing them or thinking we've done them. A second reason for not plugging in is that we want to be a certain way, to be a certain sort of person.
Someone floating in a tank is an indeterminate blob.
There is no answer to the question of what a person is like who has long been in the tank. Plugging into the machine is a kind of suicide. It will seem to some, trapped by a picture, that nothing about what we are like can matter except as it gets reflected in our experiences. Thirdly, plugging into an experience machine limits us to man-made reality, to a world no deeper or more important than that which people can construct. There is no actual contact with any deeper reality, though the experience of it can be simulated.