It sounds as though it's very unclear where the public footpath ends and your garden starts. Instead of getting all passive aggressive with people who have made a mistake, make your own life a bit easier by preventing it from happening in the future. Don't buy benches, just get a fence.
What these threads always demonstrate is that a significant number of people have no idea what a public footpath actually is, and think it's like a pavement, and that the OP is trying to assert rights over the pavement outside her house, or something.
Fences aren't often the answer, either. A public right of way can go right through your actual garden, and can't be fenced off without cutting you off from half your own garden.
I used to rent a lovely, dilapidated old cottage on the edge of a village near Oxford, and it had a small, cottage-type garden, entirely walled in, with flowerbeds, a small lawn, a little patio with garden furniture etc. BUT it also had a public right of way which came in off the village street via a little stile in the drystone wall, followed the line of the garden path up towards the house, went along the front of the house past the kitchen window, around the corner of the house, down the gable end, and out again via another stile behind the house, before continuing on across fields.
Obviously, as I was renting, it wasn't my call to do anything about this, other than to get used to ramblers passing the window, but it wouldn't have been possible to fence the path off at all without cutting the garden in two apart from anything else, part of it was on my own garden path that led up from the front gate to my front door. And the problem with legally diverting a path off your property is that it has to be diverted to somewhere and where's that? Somebody else's land? I do know of someone who successfully diverted a path that ran very close to their house, but they had a lot of land, and were able to divert it the far bank of a stream, so they had more privacy around the house, while still keeping the ROW on their own property.
I will say, though, that all the while I lived in that house, I never had anyone have a picnic on my lawn, or do anything more than walk up the path and take a photo as they went past -- I felt a lot of walkers were rather uncomfortable walking through a small garden with the house's inhabitants deadheading the roses a foot away, or doing the washing up at a window the path goes right past.
It may be that Covid times have brought people who don't understand how paths work out to the countryside more. I was certainly gobsmacked by a couple of recent threads where posters said they had no idea they shouldn't feed other people's horses.