This is a genuine question and I realize it's maybe very sensitive for those who do this, so no judgement please.
I follow a few Irish Travellers and it seems it's a very big part of their culture to visit graves and decorate them for their loved one's birthday/Christmas/Easter etc. These aren't a token bunch of flowers and a small gift, a lot of money must be spent on flowers, wreaths, toys for children. It doesn't seem the case that they leave them there for a few days and then remove them, I've seen ones who have bought a lot of toys for children for Christmas for example and they are still at the grave now. Are they just left there permanently? Again, I'm not talking about a small outdoor toy, I mean dolls and accessories, electric cars and bigger items that in all honesty I would have assumed could have been stolen from a graveyard The same with the bouquets of flowers, they are massive, loads of them and are usually very beautiful.
The only reason I mentioned ethnicity is because I've never seen this done before on this scale. Maybe it's more of a thing in Ireland? If so, does everything just get left at the grave until it's no good?