https://www.cruisecritic.com/articles.cfm?ID=1418
5. Harvest Caye, Norwegian Cruise Line
Harvest Caye opened in 2016 and represents a partnership between the cruise line and the government of Belize, which owns the island. It serves as a private outpost for Norwegian, Oceania and Regent passengers cruising through the Western Caribbean. While Harvest Caye has typical private-island amenities like beachfront villas (and unique additions like a nature center and an enormous pool), one notable difference between the island and other private islands is that there is no free buffet lunch ashore. Ships dock rather than tender, so it's easy for cruisers to head back onboard for lunch.
Your source is an upload on to the tourism boards web site. (can you say wikipedia). My source is right here at Cruise Critic and also from a Vice President within NCL.
So, No...it's NOT just NCL being cheap!!!