Are you in the US? I've never been in a salaried role in a US tech company that has a contract. And as a salaried employee who has worked at a bunch of companies, I've always enforced a good work/life balance for myself, and I've done quite well.
Yes. The specific hours aren't in the contract; it specifies following your manager's policy dictate on that matter, with some form of the definitions I gave that justify contingencies.