Ya, seen this before. Unfortunately there isn't any way to disable that. Theres a reason for that button being there. I would recommend placing the router in lockable room if possible. You can do this and if you need to run LAN wires, you can run longer wires from the ISP modem as well if there is a room that you can lock up.
I don't recommend placing the router in a metal lock box if yoru using wireless as that will impact the signal. Maybe a large wood box or cabinate, however a room that you only have access to.