Municipal services like garbage pickup are generally funded by a mix of per-household fees and property taxes. Property taxes loosely correlate with the size of the household (and yard and construction materials and everything else that scales with price) while the per-household fees can scale depending on how big of a collection can you request.

It's a good system for aligning the costs with the people who use the service.

If you thought all tax money went into a big general bucket and the government decided what services to offer out of that, municipal garbage pickup does not work that way.

There couldn't be a free delivery service because the usage would be all over the place. Someone DoorDashing burritos for breakfast lunch and dinner 7 days a week would use it 20X more than someone doing their once-weekly grocery order. Subsidizing it would incentivize a lot of waste, traffic, vehicle usage, and other things that we actually don't want to incentivize people to use more of.

The only way this could work is with a substantial per-delivery fee, which gets us right back to what we already have with DoorDash.