Ofc there is a need for it, but you don't just walk into a job and expect people to tell you this is the problem, this is how to fix it, do it. You are the guy that does that ffor the person using the computer.
If their network printer isn't being seen by by anyone in the office, even though it is switched on, has paper and ink and they were previously connected yesterday, what do you do?
You are going to roll out upgrades across the company to go from XP to 7. Do you know the best practices? How to use imagex and dism? How to install from a network if necessary, how to join the systems to the network and how to troubleshoot when you get 100calls in one afternoon because the paper pushers don't know how to use their new OS and are used to their old one.
Even if you went into a computer repair store, do you know how to troubleshoot problems, how to recover data or backup a failing drive, how to clear out a virus infested system whilst leaving everything else intact, could you give advice for setting up a users network without being sat there, looking at the screen?
Even an entry job requires knowledge about a lot of different areas and you will still be expected to have a good grasp of these things. You wont get full training, they expect you to have already done 99% of this through certifications or degrees