If it has no function, it surely would be a nice button for your garage opener. Easy to add that under the panel - I did that on my old ST1300, which had a similar button on the handlebar cluster - PO used it for his communication setup
Ah yes - I do have room to slide in next to the car. I don't use my panniers very often, which makes it easier.** if you have enough room in the garage to ride-in...I have to take the panniers off first...too many toys