"Pull up a pew" is just a colloquialism meaning something like "take a seat".Pull up a pew?? Is that supposed to be witty? It doesn't even make any sense as a pun.
Used commonly where I'm from (New Zealand), and probably in Oz and the UK as well.
Seriously, people use it all the time. "Hey mate, how about you pull up a pew and have a couple of drinks with us" etc.