Yup, Season 2 is readily available to download now.
Like I mentioned it really depends on what country you're from vs broadband speed & costs of internet connection.
When I visited California nearly 10 years ago, I was surprised at how relaxed everyone was with their broadband, leaving their comp connected to the internet 24/7...whilst back in Australia, we were still on dial-up & strictly disconnected from the net if we weren't using it because of the costs.
This is an interesting argument, why not an external hard drive? I mean, even if you pay for the movies there is no point in having the physical discs around. Which is kind of a book vs e-book argument too, except the book has more appealing features than the DVD. I assume you may not want to have your hard-drive everywhere, nor a computer, so portability can be an issue, but it's actually very minimal. The biggest value must be collectability, having a physical representation of what you own.
It is not a waste of money to buy dvd, they are good for back up but we need to give them an extra good care as once it gets damages, it would be useless. I usually buy dvd to watch movie or to burn and save files, but at this moment, I rely on streaming sites and some flash disk to save files.