The only consideration that an F1 team has (and the only one they should be concerned with) is speed compared to their rivals.
If an F1 car is pretty, but slow, it's a bad F1 car. If an F1 car is ugly, but fast, it's a good F1 car.
Ultimately, these noses are due to safety regulations. If a nose is high, and someone T-bones another person there's a chance that the nose skirts up over the side-pod and hits someone in the head. Probably slim, but possible, and also avoidable.
As an interesting comparison, how many Indycar drivers have died or were seriously injured in the past 20 years in their better looking cars? Dan Wheldon's tragic crash comes to mind instantly, and I don't think I've watched a single Indycar race myself.
You could argure that creating ugly cars is putting off viewers, but I'd argue that a death in the sport does that far more effectively. My dad hasn't watched F1 since Senna died, and when Colin McRae died (even though it wasn't in a rally car), it dealt rally in the UK a blow that it has yet to recover from.
Without the significant advances in safety that the FIA has forced upon the teams, it is likely that Webber would have been killed or greviously injured in this crash, Massa in this accident and Sergio Perez in this one.
Furthermore, if there were more precautions involved in testing, Maria De Villota may still be with us.
Everyone says that this or that is unnecessary, until something happens to someone that is completely preventable.