You can be mindful anywhere and at anytime. There are people who find skiing or other physical exercise relaxing because, after years of practice, they are being mindful in all the ways that matters to someone who sits on a cushion and "meditates". This is the end product of the "10,000 hours" thing.
The benefit from formal sitting practice is that you create a ritual container. A timebox. You align with the resolution and intent to practice. You dedicate this space, this time to the practice. However, meditation doesn't end on the cushion. You can realize all sorts of insights on the cushion, but can you integrate those insights when you're off the cushion?