why cropping a single node by deleting it from both the nodes dictionary and the features dictionary?

[bsnyh]

I'm confused about the following function.

### Crop Single Node and Feature ###
function crop!(nodes::Dict, bounds::OpenStreetMapX.Bounds, features::Dict, id::Int)
	if !OpenStreetMapX.inbounds(nodes[id], bounds)
		id in keys(features) && delete!(features, id)
		delete!(nodes,id)
	end
end

Is there any specific reason that id is deleted from both the features dictionary and the nodes dictionary? I mean, what is the relation (or is there any) between the features dictionary and the nodes dictionary?