Officials carrying flags and other equipment

[burch512]

This may be a dumb question, but...

I was rewatching the packers/atlanta football game and it looked like only two or three referees were carrying flags.

Do all of the NFL referees carry flags?

Do any of the NFL referees ever call a penalty w/o using a flag?

Also, some of the referees had what looked like black fanny packs on. What are in those bags?