Why do June bugs run into everything?

Because they're clumsy no matter how they get around, June bugs [Cotinis nitida, Cotinis mutabilis, Phyllophaga spp, Polyphylla decemlineata] crash into things. As beetles, they have two sets of wings. It's the bottom set that helps them fly around. The top set is for balance and for protection of body parts. The problem lies in the top set being very good at protection and not so good at balance.