Garage attendant uses my spare key. Change batteries at the same time?
 

So my car's been whining at me about the battery in my key. Planning to get a new battery this week just to avoid the hassle of an unexpected dead key.

Here's my scenario though. I use a parking garage where cars have to double park, so the garage attendants keeps my spare key so they can move my car if its in someone's way. Should I change the battery in that key too? That key obviously gets used less than my own.

Not really a big deal since the batteries are cheap, just more of a curiosity. Wondering what you guys think/do.

just change it as well, so you dont have to go through the hassle of changing it twice; the batteries should come in 2s anyways