In short: The waste collection fee is a local charge paid to the municipality for collecting, transporting and treating household waste and for keeping public places clean.
Simply put: Unlike a tax, the fee pays for a specific service. Its size follows the municipality's costs for that service, approved in advance. That is why it differs between towns and years.
Example: In its yearly budget a family lists the waste fee separately from property tax, so it sees how much it pays for the service and how much as tax.
General rule: Waste charges are local; some places charge by property, others by the amount of waste.
Example: Bulgaria — the fee is governed by the Local Taxes and Fees Act, Articles 62–67: the amount is set for the calendar year from a cost plan approved by the municipal council; the services and collection frequency are set by the mayor's order, announced by 31 October of the year before (Article 63(2)).
Check in your country — How the waste fee is set and paid where you live.
Source: Local Taxes and Fees Act (Bulgaria): https://lex.bg/laws/ldoc/2134174720