If you're forced to opt-in to something it creates an additional hurdle to discourage use. The same reasons some blue states offer automatic voter registration while red states have strict ID laws and keep limited DMV hours/locations for folks to obtain said IDs.

For most people, they won't bother. For those who need a plastic straw, like people with some disabilities, one is available for them. This is a real issue of accessibility for some, and thus there is a way to get one with some additional effort to request it.