I think the difference is an order of magnitude. Sea lions can get up to 2500 lbs. Harbor seals, maybe 250. So it's a wash 
Some of the seals I see around here are plumped up to the point where they look way over 300lb, not that I can accurately measure. But there's plenty of cotton candy and clam chowder around the wharf...

Some of the seals I see around here are plumped up to the point where they look way over 300lb, not that I can accurately measure. But there's plenty of cotton candy and clam chowder around the wharf...