I hear your pain!
I think everybody has/had a mate like this; ours was a bloke called Dave. He was forever short changing the bill or not putting his share into the kitty, matters came to a head when he was asked to be another mate Paul's bestman. He basically overcharged everyone on the do, including the fucking groom, so he got a free flight, hotel and days shooting!! He's now a social leper, not invited to any weddings, parties etc. he was replaced as bestman and uninvited. Do yourself a favour and ditch the leeching twat, you'll be better off and everyone else will thank you.
(The kneeling rifleman Is slowly getting there.., Mon 8 Mar 2010, 15:05, 1 reply)

The fact
that he was the subject of everyone's conversation on the Saturday night - all with tales of extreme tightness/ripping offs - has pretty much sealed that deal.
(dchurch bah, Mon 8 Mar 2010, 16:11, closed)

Fight fire with fire
Reminds me of an aquantance I had a few years back who acted like your nefarious Shane.
Solution? Prime all of the good guys next time and as soon as the bill arrives, everyone scarper, leaving the whole lot to the one who 'needs to learn'. No fuss, no debate, no calculations to the tenth decimal place.
Clean, effective and nipped in the bud.
(Said Debt, Tue 9 Mar 2010, 12:31, closed)