One: We get a look at Jerry's home life, our second real insight after the Christmas party earlier in the season. We get to see that, despite the cruelty and nastiness thrown his way at work, Jerry really has built a happy life for himself.
Two: The fact that Jerry has built a happy life for himself doesn't in any way absolve the perpetrators of the aforementioned cruelties, so there was a certain satisfaction in seeing the worst of the perpetrators, Tom, suffer some just deserts. Tom is by far the worst human being on this show, and his little sob story about having been the Jerry back in South Carolina just makes him seem worse -- he actually knows from personal experience what damage he's doing to Jerry and yet continues to do it. (At least April will take on almost anyone -- Tom restricts his bullying only to the weak.) While it kinda sucked that Tom gets to keep doing his schtick at the end, at least he got his comeuppance for being a horrible human being (in many, many ways, not just this particular case) for a brief while. It was a pretty satisfying few minutes of contrast between points one and two here.
Honestly, the hate for Jerry got really old, really quickly. When comic relief and bumbling behavior start to turn to the appearance of genuine sociopathy, a sitcom has dipped into that particular comic well way too often.
