I frequently split CS credits with my mom or friend (depending on who is on that trip with me).
At MK, the chicken-and-ribs (or just the chicken) platter at Cosmic Ray's is easily enough for two people.
Also at MK, the double burger with fries at Pecos Bills is enough to share, we just cut the burger in half and split the fries.
At Epcot, the half rotisserie chicken plate at Sunshine Seasons is again enough for two people. We also split the humongous turkey foccacia sandwich plate from the same CS place quite often.
Also at Epcot, the shawarma/combo platters at Tangierine Cafe are enough to share.
At AK, the barbecue platters at Flame Tree are again more than enough for two people.
At DHS, one of my favorite "shares" is the sandwich lunch from Starring Rolls - which is an enormous sandwich and a side (we usually get chips), plus a gigantic cupcake.
At resorts, we often share the create-your-own pasta from POR (which has also appeared at AoA now). We also share pizzas - 2 CS credits is one large pizza plus two drinks and two desserts from resort CS ("carry out" as opposed to delivery to your room), which is enough food for three or four people.