Consumers can buy seafood at the grocery on, say, any given Thursday because they know the delivery truck makes periodic visits. And if they learn that schedule on a Tuesday they can wait it out two days until the phase wraps back around with fresh(ish) lobsters.

The phase reset on a cruise has the intended effect of re-supplying the fresh(ish) lobsters but with the unfortunate side-effect of dropping you off at the shore.

Lobsters are a weird example because they're usually alive in the tank (at grocery stores around here they're the only live animals sold) so I wouldn't think "fresh" would matter much?

That really depends on the food, the grocery store, the geographic location, the season, etc.