I understand what you are saying, but there is something extra you are doing as employee #1. You're taking a huge risk not working for Cisco, Oracle, Google, etc...any of the players you know won't cease to exist overnight. The equity is offered because a skilled employee is taking a risk on you(the founder), and investing his time that could be better spent at an established company. That's how I view it at least - if you offer me equity at your FaceAppInGram startup, plus the salary I would expect from other fortune 500 offers - I might be tempted to work for you. Otherwise, there is no sane reason any engineer worth their salt would take the risk.
edit: typo