Acetobacter infections can be common but only if you're not careful. One of my batches got infected right in the primary because ALL my bottles, not just one or two, ended up fermenting to carbonated malt vinegar
That was before I switched off to using StarSan in conjunction with the OneStep cleanser. We pickle vegetables and produce in the kitchen and my primary was close by. Put 2+2 together and it didn't take long to change my brew routine.