Party City went belly up. Dollar stores are ready to scoop up its shoppers.

Dollar store chains are already seeing a lift from Party City closing.

Tyler Sizemore/Albany Times Union via Getty Images

• The collapse of Party City is giving dollar store chains a welcome lift.
• Even with concerns about tariffs and inflation, retail earnings have shown shoppers continue to spend on celebrations.
• Dollar Tree, Five Below, and Dollar General each reported good sales of party supplies.

Call it retail's circle of life.

As in nature, the demise...