W.A.R. Has Been Declared

I've been doing some rearranging around here lately, so I set my Scrabble letter "WELCOME" sign in the laundry room so it wouldn't get lost in the shuffle.  

A few days later I noticed that the "M" had disappeared.

I thought it had just gotten bumped, and that it would turn up in a laundry basket or something.

I held on to my delusions until we found a partially eaten tomato on our kitchen counter...which led to the discovery that the "E" and the "C" were missing from my kitchen "RECIPES" display.

Do the missing letters spell for you what they spell for me?

M_CE

So I bought these: 

The first night I set three traps, and two were...effective, to put it politely.

But I still kept a close eye on that letter "I" in the kitchen (and a baited trap nearby), just in case the intelligent speller had not been caught in a trap already.

Apparently I was watching the "I" too closely, because last night the rest of my "WELCOME" letters disappeared.

(I checked with the humans in the household, just in case someone was playing a joke on me.

They weren't.)

I'm baiting the rest of the traps, and I'm wondering if I should stick with peanut butter for bait, or if maybe I should switch to this:

Think it would work?