car vs plane:
An average car runs 15000-20000 km / yr, using 1200-2000 liters of gasoline. Many families in the developed world have two cars, so an average family easily uses 2-3 or 4 thousand liters of gasoline
A family trip to Rome from London (just an example, 1500 km distance, 3000km two-way) uses cca 300-350 liters of kerosene for a family of four.
Let's say that your well of average family takes two trips like this per year, that is they use 600-700 liters of kerosene vs the 2-3-4 THOUSAND liters they use in their car(s).
I still don't see why we should bash airlines so much.
Because the family in your example won't make a triple Rome round-trip per year by car.
I think it was just mentioned above that most air-travel is thousands of miles instead of perhaps hundreds or dozens by car and then if you calculate the many daily flights over 5-12000 km = 10-24000 km round-trips the math looks even worse for air-travel.
Further many passengers travel hundreds of kilometers by car to the airport and again others fly to the hub-airport from smaller airports and then the infrastructure and all
?
Railway stations for one and in most parts are neither heated nor air-conditioned, but airports are
This list i could continue endlessly and last but not least flying became a major hassle anyways. Most people only fly to acquire bragging rights and not standing behind their friends and neighbors when it comes to story telling.
Why else would anyone FLY to a overpopulated holiday resort that is either too hot and at times when climate is way more pleasant at home?
School holidays are only excuses and at the end it simply sounds better to say we go to an exotic or "IN-location" than to the beautiful places that are often around the corner.
EDIT: Out of curiosity, as much as you ask what's the problem with air-travel might be, i'm now interested to know what makes you defend air-travel so much. Either you are a frequent flyer, work or are related to people in the air-travel-business or you did not consider all the factors about air-travel but only mileage and assuming that a trip will take place anyways, either by car from Frankfurt to Hong-Kong or by airplane. (Couln't resist to use a sarc-example)