M-60E4's are still in the inventory?

I got the above pic from the Navy website. Its of a Sailor providing security on an amphib some type of naval vessel. What got my attention though is his weapon.

If I'm seeing it right, it looks like an M-60E4.

The Navy Seals and US Marines both ditched that weapon years ago and now we see it again. Does anyone have an visibility on how or why its in the regular Navy's inventory and how many there are?