Some people can't afford to stay at motels or other lodging accommodations inside or outside Yosemite. For them, camping is the only affordable option.
That said, Jerome and his traveling party don't necessarily have to backpack overnight (and secure the necessary wilderness permits) if they want to camp in Yosemite and do day hikes. As a more affordable option to lodging, I would recommend camping at one of regular campgrounds inside Yosemite, be it one of the first-come, first-service campgrounds, or trying to reserve a Yosemite Valley campground for the dates they'll be in the park
Of course, if they want to backpack overnight in the Yosemite wilderness, that's fine too. It only take less than three hours to see all the world famous landmarks within Yosemite Valley itself. The rest of the time could be spent exploring the Yosemite backcountry.
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