>Saves my time and I don't see how it hurts anyone.

Its a lie? People are looking for the equivalent of a mechanical turk in terms of putting effort into making the upfront connection instead of just being one of the numberless connections you could try and make in a night with low up front effort.

If they find out after you get some sort of relationship going that you outsourced your initial contact to a computer program, I would be surprised if it was taken well.