I bought my first eBook many years ago, before I knew the term. I had book club coming up, was stuck in my house in the country with no car, and poking around on the Internet found that I could buy and download it - immediately! It was Memoirs of a Geisha, Adobe PDF DRMed. I started reading it on my laptop and discovered this was NOT enjoyable, so as soon as I could re-bought it in paperback. So I didn't really read the eBook. (I still have the PDF, but several laptops and a new ADE DRM scheme later, can't open it)
Then eReaders came out, but were expensive and Kindle was not available in Canada. I had my iPhone when Kobo was released to market and eInk readers were now affordable. Again for book club, I bought and read The Guernsey Literary and Potato Peel Pie Society on my iPhone. I quickly saw the benefit of portability, and also having the same book on multiple devices, and it convinced me to take the plunge and get my first eReader, a Kobo.
I'm still not sure whether the convenience and instant gratification of the eBook stores is an advantage or a huge detriment!