Anything for specific providers like FB, Youtube, Netflix, Prime,Play Store, Apple , Disney + etc or general CDN providers like CloudFlare, MaxCDN etc can change end user experience enough for them to buy in.
It also has the added benefit of saving municipality upstream peering requirements and perhaps money.
Alternatively you can provide application services like OwnCloud, Jitsi for equivalent cloud products, it will be cheaper/faster etc. and target schools/community services, it may help them save on their IT bill as well.
Final idea discord, game servers, streaming servers etc can generate network effect driven interest. i.e. If i want to play with my school friends and few of them are on your servers on the municipal broadband already it is strong incentive for me to get one.