[zxcvbn4038]

A good question might be why they are not all rich if card counting is such an easy win. I’m pretty sure the best way to get rich on Wall Street is to teach people how to get rich on Wall Street. Maybe the same thing holds true for blackjack. If anyone was winning big on a consistent basis I’m sure the casinos would change things up to stop that ie table limits, six deck shoes, continuous shuffle machines.

[Zanni]

Card counting is an "easy win" only in that it's relatively easy to master. With a bit of practice, you can gain a consistent (but small) edge. The problem is, the variance is enormous. You need a large bankroll to sustain the wins, and you need to put in a lot of hours to get into the long run. That's a major reason most successful counters play in teams.

Of course you're right in that once a casino notices you winning, you're a target for closer observation. A six-deck shoe isn't much of an obstacle, though. In Atlantic City, they'll flat-bet you (adjust the table limits so you can't vary your bet). In Las Vegas, they'll just outright ban you from playing.

[cortesoft]

It has been done: https://en.wikipedia.org/wiki/MIT_Blackjack_Team

But if you are that skilled, funded, and organized, there are probably better ways to make money.