They just don't know it yet. This is still the definitive dinosaur movie. It's also one of my favorite flicks, one I never tire of watching. And that's why the movie version works so well. It's a disaster waiting to happen, Alan, Ellie, and Ian agree.
Poetic justice is, of course, in the offing.
So, disaster does eventually ensue. He's so astounded his legs give out, and he collapses to the ground. You can't help but share in the characters' slack-jawed awe at the realistic dinos onscreen. And then it gets even better, when all hell breaks loose and people start getting eaten. As a kid, I had a recurring nightmare about dinosaurs roaming the streets of my little 'burb.