The first 5-10 years a person works usually results in massive amount of growth in skills and productivity. If a company won't adequately compensate for their ever increasing value, another one will.
Annual pay raises were never more than 3% when I stayed with a company - usually 1-2%. When I swapped jobs I had a few 30% pay raises.
$16.50 adjusted for 11 years of inflation is $22.36.
So in real terms they have rewarded your friend with a 1.5% annual pay increase for 11 years of loyalty.
By swapping jobs your pay has increased by around 9.4% per year during the sametime.