What's the problem with SPAM?

First thing to consider when thinking about the dangers of SPAM email, is that we typically do not know who the senders are. For me personally, and I would assume, most people automatically delete SPAM emails once they receive them because we receive tons of them everyday, usually advertising the same products. They are irritating and frustrating, but surprisingly, people open and respond to them.
There are various reasons that make SPAM a danger to us all. One would be an attached virus. With today's technology, we could possibly be giving up very personal information to total strangers. Our computers are also in danger of being hacked or damaged, which means losing important files that we store in our computers. Not only do we potentially share our lives with strangers but also finances invested in our desktops or laptops wether it be for business or personal are being thrown out the window.
These are all avoidable if we just take precautions. Another danger applies more to one's without common sense who actually respond to these SPAM emails. When giving credit card information to unknown companies for their service or products, one should expect dangerous issues to come. If viruses can enter our computers and hackers can attain information on us, accesing our accounts would be a simple task. These Spammers steal from innocent people by offering a service or product that do not exist. People who are in desperate need of these products willingly give up account information and allow these companies to withdraw they're money and never receive what they expected. It doesn't necesarily mean that these people are losing alot of money but that is valuable information and in the long run, these fake companies would have made millions.
Its shocking to me that this actually happens. Im not the smartest guy but I figured this would be an obvious situation to avoid. It's hard enough for me to purchase products online through a credible company, let alone a company who solicited me through SPAM email. Thank God for filters that separate safe emails and SPAM, people just need to be more aware and smarter when purchasing or providing information online.