First, let us get straight with something: proxies are not a hard prerequisite for using Puppeteer.
However, doing literally anything that requires sending multiple test requests to a server bears the risk of getting yourself banned.
Bots, in particular, can be easily identified due to this, so disguising the traces of your activity and hiding your IP is very important.
Another thing is that, in spite of its well-rounded potential, Puppeteer as a mere Node.js library still lacks any means of giving your bots specific geolocation.
When given a sufficiently large scope, developers will want to test Chrome scripts’ and bots’ performance from various locations that they most likely will not have access to.
