Well, I’ve recently placed one near our cooker as that’s the most convenient place in that area.  So far it seems to be OK. But I guess if it does start getting dirty, it will have to be moved.
not sure that helps you though!!

recently I have moved house, so the kitchen is isolated with dinning room and living room, but I love to have music when I am cooking, so I am thinking about putting a speaker in kitchen :D 

I have a square kitchen, so the cooking cooking side is on the opposite of the sink side, I am thinking maybe sink side will get the speaker oiled up slower? or hopefully not get oiled up? :D 

thanks for your reply anyway! 

I have two Sonos Ones on top of my kitchen cupboards i.e. near the ceiling. They probably get a little greasy from the cooking fumes but since they are black and up on the cupboards you don’t notice it. I have one on each side of the kitcthen so it makes a nice stereo sound. It is perfect for listening to music, and probably the speakers that get the most play time, since a lot of the action in the house goes on in the kitchen. I recommend it.

it would be perfect the next gen Move stereo up like era 100, so people could take a speaker to shower, kitchen, garage occasionally, instead of wired up pair of stereos in kitchen/ shower/ garage 

As long as your shower, kitchen, and garage are covered by Wi-Fi, you can use the Move in stereo right now. It’s only non stereo when using Bluetooth. 

that totally new for me, I though move is a mono speaker :D

Each MOVE is mono. A pair of MOVE’s can be “Bonded” to build a stereo pair. This Bonded pair will appear as a single Room in the SONOS controllers.

One in my kitchen on a Sonos outlet shelf, it sees more dust than oil. If you are worried you could make a cover for it or get one of the (overpriced) pre-made ones.

Orange but other colors are out there -- https://www.amazon.com/Soundskins-Sonos-Textile-Cover-Copper/dp/B07N7716JN/ref=sr_1_3