When people approach others in the way you're describing, I absolutely don't think it helps anyone. On the other hand, I know that there are roughly 800-900 convert baptisms into my church every day, so evidently somebody was glad that the Mormon missionaries approached them.
For the record, I kind of like Mormons ... as people. I can't agree with the philosophy, but the good Mormons I knew were great people. A couple bad apples, sure. In Salt lake city, your president gave the Hindu temple there the last 10% of the fund -raising goal, which I thought was an admirable gesture. It was a place of pilgrimage for me. Actualy something funny happened on the way home. At a motel, we were discussing with the front clerk, and she asked if we saw THE temple, and we said we did. Wasn't a lie, just not the whole truth.