Good point. It is not just I want to be remote, free at my home office, yes it has benefits but also side effects. If you are new in the industry or with the company, you will have a lot of questions, and sure there will be people to answer. When in an office environment you can stop by at their desk and easily discuss something quick, face-to-face. On the other hand, when you are remote, you may not react or get they information you need as quick as possible as it would be if you were in the office. you will send an email or IM message, then the wait begins.
I have been working remote for a long time and with different companies and most of the time they want you to be in the office at least first 3-4 months to know people, warm up, know the environment and requirements etc. Then you will start with basic bug fixes etc to know the codebase, once you work on bigger tasks or projects and you need less assistance, comfortable with codebase etc. they most of the time you will be given an option to work from home partially or full remote or keep working at the office. All your choice.
Also another good thing pointed out above was not every company is good for working remotely, and not every developer is good to work remote. I think that's also another reason places I worked wanted to have you in the office for few months also get to know you.