Boy am I in the wrong business if these kids can knock out CRUD apps for $100K.
If you are serious about web apps, then scaling the back end comes into play, which means getting into distributed systems. Networking, security and SysAdmin become relevant as well.
I think it's fair to charge up to $100K with a college education and/or work experience in the field. Other professions do so as well.
Go pick on other professions: i.e. banker bonuses, real estate commissions, union rates, lawyer rates etc.
Although, I admit... this example is really just a CRUD app, with no advanced server back end.