There is a difference between being told you cant do something you have always done and wanting to get into something new. I have only been without a motorcycle of some sort for about one year since I was 10 or so, so my wife knew going in what I was into. Say I all of the sudden decided to take up skydiving. I would think that would be something to discuss with the wife. Would weigh the pros and cons and come to a decision that was good for both.
Luckily for me the wife doesnt tell me no very often. I just put the thought into her head and she ends up into it as much as I am. That is why I have too many bikes now, just cant bring myself to sell anything.