When receiving a publisher offer, you have to consider what path you want to take. I speak purely from the perspective of an English author.
Traditional publishers will print books on demand for new authors, so the offer will be for just a small quantity to be issued to mainstream bookstores who have to then sell them before any more are printed. Lots of bookstores welcome new debut authors to sit at a desk and sign their books as it draws people to their stores but usually this is arranged locally, at one store. The offer may include eBooks but a lot of traditional publishers focus on what they know best and the push will be for their more established authors.
It may sound glamorous but the reality is that if the book does not sell then only the initial quantity will be printed and it will not go abroad. Some authors may be happy with this because they have produced the one book and fulfilled a dream.
An eBook publisher will focus on all new technology available to readers and it is not a simple job of just converting your manuscript, as numerous software versions have to cater for each eBookstore's requirements and anti-piracy stipulations. Also, your publisher has connections and knows who and when to target.
So - as a potential author, is your ego telling you that only printed books will be acceptable and you look forward to sitting at a table and signing books, or are you looking to the future?
My decision to go down the eBook path was purely a personal one, after also considering offers from 2 traditional publishers. People will continue to buy printed books and eBooks, as do some people who still like to buy CDs or vinyl. The times, they are a-changing and as people change how they live, they also change how they read.