Women with a high hereditary risk of breast cancer sometimes opt to have both their breasts removed pre-emptively. People take statins and blood pressure drugs for years to prevent heart attacks. Don't you have eye tests and dental checkups on a precautionary basis? There's plenty of preventative medical care.
Maybe the availability and marketing varies between countries - the fact that you assume people have to invest their own money to ensure their health suggests you're from the US or another country with a bad healthcare system. My country has a national health service which takes an interest in encouraging preventative medicines like statins, helping people give up smoking, and so on, since that saves it money overall. I'm sure the allocation of preventative care is far from ideal and shaped by political and social factors and drug company lobbying, but it does exist.
It would be a bad tradeoff to go through painful appendectomy to prevent the small chance that you might get appendicitis (and you can get your appendix removed when it's actually infected, and the appendix may have an evolutionary function acting as a reservoir of gut bacteria, and it can also be used to reconstruct the bladder).
Don't you have eye tests and dental checkups on a precautionary basis?
I tend to view there as being a strong difference between "go for a 2 hour checkup" and "invest $28K in cryonics". I wasn't aware of the pre-emptive breast removals, though, that would definitely qualify as the sort of thing I was looking for - and I still wonder how common it is, amongst people who would benefit.
the fact that you assume people have to invest their own money
I'm not aware of any country whose socialized healthcare pays for cryonics, so cryonics...
From Mike Darwn's Chronopause, an essay titled "Would You Like Another Plate of This?", discussing people's attitudes to life:
Conclusion, graphs, and references in article. As usual, I recommend reading Chronopause.com as Darwin has many good articles; to quickly link a few: