So Torswats said that Piggy owed him $250, because he paid half up front and was supposed to pay the other half afterwards, and never did. He said that Pig had paid reliably all the other times, which was why he let him continue with this arrangement.
That means, if we take $500/SWAT, and say that amount was paid for 20 SWATs, we're looking at someone spending $10,000 to SWAT Pat.
So look at this from two angles - either someone hates Pat enough to spend $10,000 annoying him/trying to get the police to kill him AND actually has the money to do that, or Pat has spent that money himself. Pat doesn't look like he has that money to spare, but he also doesn't look like he has the money for constant vacations, a $1,800 smart phone that he promptly destroys, or $3,000 tickets to A Christmas Carol (or however much we figured he paid for those). Whatever mess his finances may be, he can clearly find money from somewhere to spend in an absolutely wasteful manner. And he seems to be motivated to spend it all as fast as he can before Quasi can get to it.
At any rate, knowing the cost of the SWATtings, and knowing the dates when they happened, it seems like it should be possible for someone to go through Pat's finances and see if there happens to be a pattern of $500 expenditures at those times.
I think there's still room to suspect that someone other than Pat is behind the SWATtings, but not a whole lot of room. Pat is enormously fat, after all, and takes up most the space in every room he enters.
edited for grammar