Left on a wall

I spotted this mask on a high wall on my way home from work tonight and I am not impressed as there is so many of them now just dropped everywhere on pavements, roads, floors, it's actually quite shocking to say the least.

My point is why people just can't put them in a bin as masks are now being used to provide protection from Covid. I am guessing that this is kids I somehow don't think adults would leave a used mask on a wall ???