[shultays]

Does this add a bias though? If I took first card in deck and swap it a hundred times more than others how would that make a difference?

[dalore]

Yes it does. http://blog.codinghorror.com/the-danger-of-naivete/

It's random but some results are overrepresented so more likely to occur. If you knew this and bet on this over time you would gain an advantage