We don't need a lot of things. A better example than plastic straws is beef: we definitely don't need beef, it's already expensive, and it has an extremely large and disproportionately heavy impact on CO2 consumption due to the combination of required grain, methane release, and needing land for cows incentivizing cutting down rainforest. Most people here would be pretty up in arms about any proposal to ban beef, so why focus on comparatively harmless stuff like lipstick and soda?