Or probably they choose those exchanges using Coinmarketcap rating? CMC still rates p2pb2b as a top exchange and that's very confusing and annoying.
If the developers see exchange rates in CMC, then they will be wrong in evaluating them and they will get stuck on bad exchanges, because if I look at exchange rates, I agree more on coingecko sites than CMC sites.
Some project team don't even know the difference, they only find exchanges that won't charge them much for listing
If the developer or team is looking for exchanges that do not burden them, then their token values will quickly be destroyed and their projects will also be difficult to develop, it is better not to make projects so that the burden is not there, rather than having to choose an exchange that does not burden them.