While it's a minor thing, Earl's rather cold remark about the event in the sequel seems at best, in bad taste.
Julio's death in Aftershocks is even more disturbing, as he desperately clutches at Kate for help while being dragged from the window. His screams are still audible as she's ducking for cover, accompanied by horrific crunching noises.
The vocalizations of the shriekers are rather terrifying.
Bad enough dying by a Grabloid but to first be trapped inside your car and face being buried alive or eaten like the doctors poor wife did, brr.
During Tremors 2, our heroes come across a dying Graboid. Few scenes later we find out that it and its kin have been TORN OPEN, letting out three Shriekers each. As a kid , I instantly made the connection to skinned beans, and how there's a few pods in each of them. Seeing the Graboid's final moments and then its carcass was pretty disgusting and scary. The fact that the Graboid species has that kind of brutality built into its very lifecycle is chilling in a way beyond standard gory murder, going into Alien territory.
By extension, the entire night section up to the Shrieker's reveal is one big chilling case of Nothing Is Scarier.