According to the US Small Business Administration, about 24 million small businesses operate in the United States today. Small businesses like email as an advertising medium because it seems to be so inexpensive.

Let's think about that 24 million number again. If every single one of them decided to send out a pile of email advertisements today, it would be a very bad day. It's probably not reasonable to suppose that would happen, however. It is probable that each year, one percent of the small businesses could decide to send out an email advertisement to everyone they can reach, and they conveniently pick different days during the year. Leaving the arithmetic out, that works out to more than 650 email ads per recipient per day.

Ouch. That's pretty rough. We can fairly say that we really don't want all of the small businesses in the United States to think it's OK to send their ads out via email.