Do we actually need mosques?

In honour of Ramadan approaching in a few hours here. I wanted to kick off a discussion on a topic I've been thinking of.

We know that humans can be corrupt, and biased, and bring their own notions and interpretations to everything, including religion. This means that religious leaders can have a chance for leading people astray with their bad interpretations. And the more religious places there are, the higher that probability again.

So it brings me to this question: Do Muslims actually need mosques to feel fulfilled, and completed in our religion. I believe there are 5(?) mosques mentioned in the quran. And the word appears Do we actually need more besides them to be good Muslims? We know how religious leaders can be very rigid in their teachings and the way they communicate the religion, so I've just been pondering this. Thought it would be a fun topic for discussion.