I suspect the mom-to-be is undereducated. It may or may not be too late to change things for her, and, more importantly, her little baby. I was deadset against co-sleeping before and when I was pregnant (undereducated and misinformed), but hearing people talk about the benefits (and realistic, not overblown, risks), then later reading the dr sears ap book opened my eyes to it - but not completely until she was 3 weeks old or so. Now I can't stand to sleep without her.

I think it is so very important for her to know that her pastor's wife breastfeeds, thinks it is normal, and assumes others are going to do the same. When someone tells me they are formula-feeding or giving solids very early, I assume something must have been wrong for them to do this and ask exactly that. I would encourage you to approach the issue in whatever way you are comfortable, but I would like to add that you are obligated to do something because you know better. If she was planning to drive around in a car with her new baby in her lap instead of a car seat, you wouldn't hesitate to educate her, would you?
BTW, I think your standard shower gift is fantastic!