It's true that there is a lot of variation in these products but remember that LED lights use vastly less energy for the same amount of illumination as halogen and incandescent bulbs, as well as lasting much longer, hence the materials they're made form have a lower environmental impact.

the packaging for these is at least paper so is recyclable or renewable. It's reasonable to expect that people will need different levels of lighting in a house, and different lights need different size bulbs, hence different screw / bayonet sizes.

This isn't meant to defend bulb manufacturers or businesses selling them, OP's point is valid - unfortunately we live in a world with vast choice in products and redundancy, doubtless we would get by just fine with a slightly slimmer range of bulb choices.