The CS interview problems that are asked are a very specific view of CS that not everybody finds interesting or works on. There is a lot more variety to CS and

The CS interview problems that are asked are a very specific view of CS that not everybody finds interesting or works on. There is a lot more variety to CS and software engineering than string and graph algorithms, which is all I've ever been asked at Google (where is numerical optimization, statistics beyond basic counting, all of graphics, etc). I also never get asked anything with regards to actually engineering software by them, whereas I have been asked that at Apple for example.