I'm a solicitor and I speclialise in challenging wills and making claims for reasonable financial from estates.
There are many cases where, with modern family set-ups, second marriages etc, a cohabitee or young children don't inherit. What if you've been living with someone in their house, not married, have young children, and they die without a will? You get nothing.
What if an elderly relative, who is reliant on neighbours for help, is coerced into changing their will?
What if you gave up a job, and moved in with a parent/grandparent to care for them on the understanding that you would inherit their house but the will doesn't say this?
For as many people that say they/their partner won't take any action, there are those that need help.
It's always worth having an initial chat with a solicitor.