Well, Bitcoin developers listened and they created side-chains to facilitate cheap and instant transactions via the Lightning Network and now we see how these advancements are used to pay things like highway toll fees.
Where have you seen even the smallest mention of this using LN to pay the toll fees?
There is no side chain, you deposit bitcoins and the exchange converts it to fiat to pay your bill, there is no "sidechain", it's a bank chain because the actual payments go from the exchange to the authorities via normal fiat transfers.
The advantage is, when the price goes up, you only have to pay less.
You till pay the same, there is not paying less or more, yous till pay 100 rupiah or 10 dollars, because your coins are worth more.
Just because bitcoin has risen 10 000 times in price it doesn't mean bread is 10 000 cheaper now for you.
You actually have to pay more because they are going to charge a fee on the conversion rate and to cover the spread, the actual purchase might be fee-free but till there you have to pay extra, do you think they would be offering this service just out of goodwill and not try to make a few $ extra themselves?