There's a good point here. Whilst most pax like the odd PA from the Flightdeck when appropriate, the constant jibber from the cabin PAs visibly irritates many pax - with the volume set on 'high' and a noticeably fatigued voice not helping matters.
It's even more noticeable on low-cost carriers - some cabin crew are so sick and tired of getting promotional PA memos that they simply don't bother anymore...I say leave the propaganda to the inflight magazine dept....