There are two types of pebble mix. One is the old glue on type and the other is what is often called exposed pebble mix.
The old glue on type of pebble mix is rarely used these days as it is known to degrade leaving an unsightly mess.
Exposed pebble mix is created by spraying a concrete retardant onto the wet concrete. This prevents the surface from going hard so it can then be pressure washed off to expose the stone. Exposed pebble mix is good for grip on car tyres but can actually be quite harsh and feel sharp underfoot.
CCC Acid Etch on the other hand is good for grip but is also easy underfoot. Nothing really compares to a well done Acid Etch finish where a non-slip concrete surface is required.