Generally speaking, I don't think so. Much of the cost of the character meal includes the character interaction. Some character meals have been known to charge a $10 "character experience" for those not eating instead of the whole buffet cost though.
Maybe if anyone has done this at CM's they will respond.
A few years back, we had traveled to Disney with my in-laws. We went to Minnie's Menehune Breakfast buffet (which we loved!). Anyway, FIL only ordered a coffee, and was charged the price of the buffet. My MIL was so mad with him. But that was all he wanted - and to see DDs face as the characters came around!
Don't know if things have changed since then though.