Littlestone has it right I reckon, you should only "own" the monument for as long as you're there. That's the perfect compromise, surely? And it provides an adequate answer to Alfrede's question:
"I would be interested to hear who gives you the authority to decide another human beings personal offerings are 'detritus' and 'rubbish'?"
Alfrede, it's a personal offering while you're there but it's unappreciated detritus after you've gone!