The drive to understand has many influences, some want to understand this world, then some people learn stuff to better understand their diety.Chances are the what drove Mendel is exactly the same thing that drove every other scientist, the drive to understand, that has nothing to do with religion.
only if you are fundamentalist. Most christians, and in fact muslims, are not fundamentalist, and consider some things to be merely the superstitious ramblings of 3000 year old jews.Religion did not help science because it DENIED naturalistic explanations in favour of divine ones, science seeks to explain the universe, religion already has all the answers.
The thing is, Neither of us can have evidence to support either of our claims about people doing or not doing for religious reasons, as we werent there, and we arent inside the people's heads.
All this "religion has hampered science" stuff is based upon catholiscms hate for anything that threatened there power over the individuals that were part of the religion. Now, in that case, for the most part, christianity for around 1400 years was hampering science. But as the Protestant reformation came about, and people actually read religious manifestos' etc., they had more inquisitive minds.
But as i said, neither of us can prove our claims, except by saying, "well, such and such was done by such and such scientist, and he did it because of such and such reasons".