it doesn't have to track bitcoin or cash. it tracks overall transactions. you can't have multiple trackers going on selling fromt he same lot of tokens. otherwise, you would risk double selling the same token. there has to a CENTRAL transaction count for all of them. etherscan tracks OVERALL transactions for tokens and icos. all you have to do is look at their numbers for other icos like vibe or trx or ripple and you will see their "transaction" numbers match those of other sites that account for btc and cash exchange, etc. you would have confusion if they didn't track all of the transactions.
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