I imagine that services can be grouped with other relevant services. For example: Bike Chain Installation + Bike Chain Lubrication.

I would rather pay someone to do that than to do my laundry or my coffee--but I see your point.

They didn't know they did until they heard someone would do it for you. And for more than the whole bottle of lube costs to boot.

Probably an add-on item in a tune-up bundle that will show up when you buy a new bike from Amazon.

Weirdly enough, yes.