The quote 'the best things in life are free' has become a bit of a cliche, however the reasons cliches are so widely used is probably because people still find a lot of truth to them. It is often used when discussing issues such as love, nature or independence. It is true that love for one's family is 'free' in the sense that it can't be bought, but that is only telling half the story. A happy, fulfilled and nurturing family needs certain conditions in order to thrive. It is far more difficult to provide nurturing conditions when issues such as fear, job security, hunger or poverty are pressing down on the whole family. Debt can cause misery, anger and disagreement too. A family which is fortunate enough to have a secure breadwinner and doesn't try to overstretch itself to gain material possessions can usually provide a happy home for its members - and the love that will thrive there is surely free. However there will be cost even there. Priorities have to be set, family members to be consulted, agreement to be reached, basic living costs to be met - otherwise there will be discord.
Families can enjoy many things together at little cost, but even many of those things are proving to be out of reach to poorer families. A picnic in the park may not be possible for a family that cant afford a bus ride out of a concreted tough neighbourhood for example. Another would be a trip to the woods or ocean - fuel costs money. It may not be possible even to sit out on porch or street in the sun together in some challenging neighbourhoods due to safety reasons. So yes, many of the best things in life are free but the issue is not so black and white - there are many compliications.