The veteran engineers from the company's earlier days are often true-believers in the company/product, and probably joined for below-market at a time when market rates were lower. As a result the comp structure at these companies gets into a really weird state where a new market-rate junior hire cost about as much or more than the seasoned technical staff they already have on payroll.
That's a tough pill for companies to swallow, and even if you do manage to hire you'll have a mutiny on your hands if you don't do something quickly to close the 40+% gap between the comp your existing employees are getting and the market.