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No, there is not really a benefit by having an own token. They still would have to find a way to generate revenue.
99% of all tokens are just worthless money grabs. For dapps it's basically a way to do fundraising, but then they don't deliver. Just look at this list, it's a joke:
https://steem-engine.com/?p=tokens
BTW, how do you think that dapps make money? You only can when you receive more than you give back to users. That's why delegations etc. are never profitable for the users. Purely financial speaking, it would be better to sell your votes instead. There is always someone who is paying the bill. In the case of Steem, it's the whole community who pays for upvotes. In the case of dapps, it are the users/delegators themselves who pay the bill.