There are many computer science principles that are relevant to even a CRUD business application, encryption, hashing, caching, parameterization, abstraction, design patterns, and more are all applicable to problems for those kinds of applications -- they're just rarely used.
Also recognize that CS is a much newer science than physics. Some of what you are saying may be due to the immaturity of the science, but it doesn't mean that it isn't engineering.
I took a lot of other engineering courses including statics and dynamics, thermodynamics, electronics and courses for premed requirements and I don't see a lot of difference between computer science/engineering and biomedical engineering or civil engineering except our perception of of the physical engineering as more important -- due only to their visibility.
CS/CSE is hidden from view. People don't understand where while loops are operating, but they can see gears spinning and cables holding up bridges.
Compare typical software projects to medical software products as a niche. Much more design, time, and money is spent there than on Web 2.0 sites because lives depend on it.