Dear crypto.piotr,
DLease is not a 3rd party, both DLease and Steemvoter are services by BuildTeam. That is a little bit like Gmail and GDrive, both are owned by Google and thus linked with each other.
If BuildTeam was using your vote to upvote, for example, Utopian or SteemSTEM, then you'd be correct. But the current usage is stated in Steemvoter's ToS.