"Could you bring up this issue to the speaker at the meeting?"
I don't think it's appropriate to bring up competitive pricing when someone is willing to come and talk to us.
His subject will be, what does it take to open a fish store?
IMO: It's not cool to start price bashing / hounding, comparisons when they are gracious enough to come speak to us.
If you don't like the prices, then shop around elsewhere or go bring it up at the store location,
but the club meeting is not the place, nor the time.