The real reason to hold Gold and Bitcoin is human tendency to secure future or to fulfill security needs compromising present.
Due to sky-rocketing inflation, mere savings won't gonna help developing capital for person. Certain contingencies like accident, etc can shake the entire budget of individual. Hence, to stabilize one's financial position and to give catalyst impact to savings, person goes for investment in gold and bitcoin.
There many are reasons why people hold their bitcoin and gold. The real reason why people hold their bitcoin and gold because there is a possibility that the price of bitcoin and gold will increase day by day in the near future furthermore, they hold it gets more income and holding is best strategy if you want to a high income.