My husband and I were equal partners in life. We didn't "allow" each other to do things.
That said, my husband intensely disliked and feared snakes and he asked that I not keep snakes. He was okay with all the other things I did and kept and because I respected his feelings, I never got a snake while he was alive.
Now though, I have plenty. And monitors, tegu, etc. I don't have to worry about anyone saying "I forbid!" to anything I want to do or have, and I haven't worried about that since I moved into my own place as an adult.
If you share your home with someone, it is only respectful to sit down and discuss things. Just as they should take into account how much you want to have this hobby, you should be taking into account their feelings. If it's fear, find a way that it doesn't bother them... use a garage or a single room or even a different place(friend's house). If it's money, then figure up the budget and see where you can cut YOUR expenses, i.e. don't eat out or take your lunch to work, or stop smoking or don't go out drinking... etc.
Deal with it like a rational adult and there should be some way to work things out so that everyone is happy!