To shake a stick at:
The phrase is fairly old. Its first recorded appearance is found in The Lancaster (Pennsylvania) Journal in 1818: "We have in Lancaster as many Taverns as you can shake a stick at." The sense then, as now, was "a lot" or "too many to count."
http://www.phrases.org.uk/bulletin_board/5/mes sages/481.html
A large quantity, more than one can count, as in Our town has more banks than you can shake a stick at. This idiom presumably refers to brandishing a stick as a weapon, but the precise allusion is unclear. [Colloquial; c. 1800]
http://www.answers.com/topic/more-than-one-can -shake-a-stick-at
more something than you can shake a stick at (old-fashioned):
a very large number of something. "I don't know why she wants more shoes - she's already got more pairs than you can shake a stick at".
http://idioms.thefreedictionary.com/shake+a+st ick+at
A LOT, Many, tons, too many
"At the protest there will be more hippies that you can shake a stick at".
http://www.urbandictionary.com/define.php?term =more+than+you+can+shake+a+stick+at