When you post please always provide the full version of sql developer you are using and the name and version of the OS.
What versions of sql developer and windows are you using?
How did you perform the sql developer installation?
I can confirm my Oracle 188.8.131.52 32-bit install on Windows 7 has a Start menu SQL Developer shortcut advanced property of Run as administrator.
Not sure why, but you can find many discussions in this forum where users had to Run as administrator to get the product to run.
That seems to be the exception rather than the rule. So for your second question, which I would rephrase as "Is it safe to disable that property", I have to say probably. Why not give it a try?
Working off of memory, which is always dangerous, but I think when you go to load the Oracle client, it can cause problems if you're not an OS Admin. So if you're going to use OCI/thick connections in SQL Developer, this MIGHT be necessary.
Actually, going through the motions of getting that old 1.5.5 install to run OCI/Thick (which entailed replacing the default ojdc5 jar with ojdbc6 from the Oracle client and switching to Java 6 from Java 5), the only requirement for Run as administrator was getting write access on sqldeveloper.conf so the Java path could be updated.
If SQL Developer is installed outside an Oracle home, then I suppose there would be no reason whatsoever for Run as administrator privileges.
Another possible requirement for Run as administrator is to change file associations.