Sounds like a novelty indeed, usually you would expect a slicer for that.
About the lettuce; the silver and the lettuce will react chemically to a poison (atleast when the silver gets "chipped" off the silver fork by the knife). That is the reason why etiquette dictates one should never cut lettuce. It is however just a left-over from the days when people who could affort lettuce ate with silver cuttery.
Nowadays hardly anyone uses silver anymore, so it should be perfectly ok to cut lettuce.
Something similar happens with egg and silver.