You are not likely to get a statement from them, but you never know.

One of my goals each season is to get no reds on my BvB, I've managed it a couple times.

Do you use a lot of arrows? I find some players don't respond well to arrows. Also I find a 2* vs. a 6* will make both sides more likely to get a card, though there are exceptions. Having it on normal, isn't the only thing, some people don't get cards with it on forceful, so look at the players that don't get cards and see what they have for attributes & orders and look who does get booked and see if they are much different. I have an idea of how I want the various roles and try to add points to get them closer to that.

As far as penalties go, I usually choose the guys with the best finishing & shooting, and guys with the SA. Even a GK can take penalties!