I used a summer sleeping bag that was 14 oz after I cut the zipper off (Marmot Pounder, which I wish they still made).
I had a "blue foam" sleeping pad that was cut down to size, which is extremely cheap and light. I now opt for much heavier sleeping pads. When cowboy camping along the AT you do not need much of a sleeping pad because you'll likely be on top of leaves, but on a shelter floor it's not enough.
For shelter, I just had a 6 oz sil tarp for when an AT shelter was full and I expected rain. I set up the tarp exactly once, and it didn't rain anyways.
My spare clothes were a spare pair of socks, a fleece shirt, fleece gloves, and a fleece beanie. None of those were expensive. I had a $0.99 plastic poncho for rain gear.
I did not cook, so no cooking gear. I had a digital camera which I barely used. And then just small stuff like toothbrush, water treatment drops, etc.
My base pack weight was like 6 lbs and change, and I had a tarp and camera I wasn't really using.
So, yeah, you can hike extremely light and not spend a lot of money. It depends on what trip you are doing. I started very late in the season, so the weather was warmer and shelters were not full.
I resupplied food in towns along the way. And while in town, I had a hot meal there. Also consider that resupplying is often not done in an actual town, but in a convenience store or whatever is closest to the trail.
Backpackers typically only cook dinner, and those get repetitive, so forgoing those with the added benefit of not carrying a stove, fuel, and a pot is sometimes nice. Some people find it wearisome to not have at least one hot meal a day.
Of course, I have done countless backpacking trips and have cooked on most of them.
We haven't even gotten to clothes.
Edit, to add: or you’re not counting all the gear your pack animal is carrying.
Sure, if you really are in the wilderness. But if, like so many of the weight weenies interested in UL gear, you are hiking a well-trodden trail where water stops are frequent and well-mapped, no one is going to lug that weight until the end of the day when they might fill up for cooking with.