House Project: Aren't Towel Racks Normally Screwed Into Studs?

My daughter is visiting, grabbed the towel, and pulled the towel rack right out of the wall. She's not exactly a female version of Governor Schwarzenegger. It appears that the towel rack is mounted to the drywall using a rather large type of plastic screw. I'm very disappointed, and I've emailed that disappointment to the builder.

Last house project entry.