Pauline Kael called it 'cold-hearted'. She was right. *SPOILERS*
Sarandon's character gets killed, and how does the film react to this?
By having all the remaining characters sit around moaning about what a downer this will be for their careers. Even the girl's boyfriend isn't as distraught as you might expect - he's rather stoic, considering!
I also couldn't understand why he, the pilot, didn't just skim a lake and tell her to jump into the water whilst he passed over. Hell, we've seen him crash into a lake before and emerge alive - with a leg in plaster, but alive! Had the film nixed this as an option (maybe by having her repeat the famous Sundance line, "I can't swim!") I would have had far more respect for that scene.
Goldman's script for BC&TSK featured the callousness-as-machismo motif (the whole "can't help you, Sundance, you're on your own" thing, for example) but that was tempered by a genuine closeness between the two guys. That human connection is lacking in TGWP, resulting in practical jokes that come across as nasty (getting rid of your rival's wheels? OUCH!) and in a finale that demands we see a healthy thirty-one-year-old man as a failure who needs to go out in a blaze of glory. Spectacle over humanity. I'm really not surprised it bombed at the box office.