I just don't get it.

VelociMama

Why are butter, cream, and PB unhealthy?

All of these are calorie-dense, which is good if you've got the calorie budget for them, but if they take the place of nutritious vitamin-rich foods in a limited calorie budget, then it can be an issue with not getting enough nutrients throughout the day. Personally, if your calorie budget is that strict, you should consider raising it. Full fat butter and cream add much-needed fats to your diet. OP really has room for both with all the exercise calories she has available.