What stops people in this day and age from being self employed?
Millions are self employed keep that in mind.
^inegalitarian distribution of capital in a society that rewards the ownership of said capital
e: for example, the barrier to self employment is basically the same barrier which prevents the fry cook at mcdonalds from opening a competing restaurant across the street (though depending upon the situation, this may be a much larger scale example)
I quoted both of ya because I want to answer pstalls question and believe it or not Godspin makes a decent point.
Nothing in theory is stopping someone from opening their own business, but several things in reality are.
The easy and popular answer is you can bootstrap your way into wealth, but the reality is the cards are stacked against you.
If that fry cook wants to compete with McDonalds he needs a way to access supplies/labor/location at the same price as McDonalds. This is virtually impossible. Not to mention how many banks would give a big loan to a fry cook with a dream?
The problem with "Well groups of small businesses should just co-op together to fight the man"
is simple. Folks can't agree to poo. ME ME ME ME always destroys WE WE WE WE. Granted sometimes such things have worked, but they lack the pure $$$ muscle and single minded make money at all costs approach that a big corporation has.