I get metrics for all of the topics but I don't see all of the consumer groups

I get metrics for all of the topics (i see all of the topic names in the metrics list), but for some reason not for all of the consumer groups.

No file, test, or entry point is identified in the report. Start by reproducing the difference between topic and consumer-group metrics, then trace the metrics collection path for consumer groups in Burrow. Done means identifying why some groups are absent and adding coverage or a verified fix for the reported behavior.

Written by the indexing model from the issue text.