If an individual person doesn't like having roommates, then that's entirely up to them. People who don't like roommates tend to make bad roommates anyways, in my experience (there's nothing like living with someone who resents your basic existence), so it's a better option all round.
But there have been some people who seem to be saying that having roommates is an inherently bad thing and the only way to not end up in a horrible roommate situation is to live by yourself. And that's not my personal experience - I've had tons of roommates without major problems, and I have had situations where I've deliberately gotten roommates because, for me and in those circumstances, it was better than living alone.
Come to think of it, the only unpleasant situation I've had was the one year I lived alone. It was in a grotty, tiny, very dark, unairconditioned basement suite with once a week laundry access. The carpet was ugly, and wasn't even a whole piece - it was bits left over from another project trimmed and used to tile the floor. The bathroom had faulty wiring. And the landlady had no understanding of landlord-tenant rights (this was a legal suite) and would come into the place whenever she felt like it, and re-arrange stuff to suit her, and object to me having people over to visit. And this cost me 40% of my post-tuition salary.
And when I decided that I didn't like it and would rather share, I had to wait out the full year lease before I could get a place with a roommate, when for the same price I was sharing a bright, spacious two bedroom apartment with an amazing view and only minimal roaches.
