When you work full time it's hard to go back to school after you start making enough to support yourself. The only way I would be able to go is online courses. But in all fairness,neither way is easy when you work full time.
People who criticize online education should realize something: there are your Harvards, Princetons, etc. and there is everyone else. Simply for convenience, online gets the nod. It is all about the money and piece of paper anyway.