Chains are not maintenance free in many cars.
They can require regular replacement and some are extraordinarily expensive to replace when the time comes. Modern Audis, for example. Timing chain on some Audis is several thousand dollars.
Some classic Mercedes V-8s require engine removal in order to replace the chain, and it's good for about 100,000 miles. Engine removal to do a chain is a whole lot more than that Honda mechanic was going to charge you for a belt!
My 1970 Ford had a 302 V-8 that jumped time due to timing chain wear. Small block V-8. Jumped a tooth (took a while to figure out my no start condition, that's another story). A stout chain, made of steel, running on steel gears, but with nylon buffers to quiet it down. Nylon wore out and it failed at about 120,000 miles.
The "Good ole' days of timing chains" weren't all that good when you look closely.