Why do you turn Jews away instead of being mekarev them?
The early Zionists weren't religious. They were anti-religious. Yet you expect them to uphold what the Gemara said about not taking the land of Israel by force.
However, people of your persuasions who claim to be devout followers of Yiddishkeit stumble over much more important and basic tenets of Judaism. Instead of bringing Jews close you just frighten them away.
The entire essence of Anti-Zionism is as futile as throwing dust in the wind. Anti-Zionism doesn't change a thing in the real world and in fact just makes a curious anomaly for the Gentiles to laugh at.
Do something positive
The early Zionists weren't religious, but later many were, and it is those religious Jews at whom we aim our material about the taking of the land by force. We want religious Jews to separate from this movement so that the true followers of the Torah will not share any of the blame for it. Yes, we want to bring Jews close, but close to what? Close to the real Judaism, not to Zionist Judaism. If we were to keep quiet about this issue, we would be allowing a fundamental change to occur in the Jewish religion, and all Jews who become mekurav in the future would be joining a different Judaism.
Besides, many potential baalei teshuva are being turned away for exactly the opposite reason - they are not comfortable with Zionism. They need to hear about us.