They also have email hosting for $ 2 per account per month. Do you know what's the difference? What's the advantage if you can have unlimited e-mail accounts with web hosting?
Original reply:
Buying domain hosting gives you "unlimited" email addresses, so domain hosting is cheaper as soon as you need 3 or more addresses.
3 addresses x $2 = $6/mo for email vs $4.95/mo for any number of addresses. I have a friend who is married with 4 children. He pays $4.95/mo for 6 addresses. You don't have to actually host an http domain to get email hosting that comes with domain hosting.
"unlimited" in quotes because obviously there are some limits and service terms. You can't start a competitor to gmail with a $4.95/mo hosting account.