Statistics New Zealand says there were 600,000 over-65s in 2011, and that will increase to 1.1 million by 2031.
Mum and dad investors could invest in publicly listed companies only, but McCaw has capital in privately owned companies.
Companies Office records show McCaw first invested in retirement homes in the mid-2000s, jointly with a company called Banco Trustees Limited. He took out a 1 per cent stake in Oakwoods Lifecare and Ashwood Park Lifecare in 2012, before taking a stake in Bainlea House retirement facility in Rangiora last year. McCaw's manager, Dean Hegan, told the Herald on Sunday the player preferred not to speak about his personal investments.
Carter, who owns shares in seven aged-care facilities, has previously said he got involved on the recommendation of a friend who worked in the sector.
McCaw earns an estimated $650,000 a year from the All Blacks, plus endorsements and sponsorships, and is a director in several investment companies.
Last year the 33-year-old, 124-cap veteran became a director and 14 per cent shareholder in Global Renewables, which sources and supplies wood pellets for heating.
Fellow former All Blacks investing in aged care include Corey Flynn and Aaron Mauger.
Most top All Blacks have their wealth invested in properties and investment companies, keeping their true net worth under wraps. Personal wealth expert Lisa Dudson said anyone considering an investment should first understand how the business was structured, and what the returns were.
McCaw has said he will continue playing until next year's World Cup in the UK, barring injury or a major slip in form.