you can test it yourself by logging in as a non-root user and playing with the "ping" program

The "ping" utility is always setuid root:

[Quoose:~] xmath% ls -l `which ping`
-r-sr-xr-x    1 root     wheel       24920 Dec 23 15:17 /sbin/ping
[download]

That's why normal users can use it. :-)

Update: it seems that lately raw sockets are no longer needed for ICMP on some platforms (Darwin / Mac OS X); but on most (Linux etc) they still are