I guess a lot of us get spam to some degree, no matter how careful we think we've been regarding who we share our personal email address with.
I even have a Hotmail account specially used for forums, websites and traders. You should see the junk it receives: 200-odd items a week, all filtered out for me by the Hotmail junk filter.
But, I never thought I'd see the day when spam started to appear in my iCloud in-box. The iCloud mail account was given to me by Apple even though I didn't ask for it, I've never used it, I've never given it to anybody and I've never quoted it on anything. In fact the only reason I even see what's in it is because Apple added the account to my mail client automatically. How thoughtful.
For months it lay dormant other than an occasional email from Apple themselves, then even they dried up. Suddenly, twice over the past week, it's received spam mail (spam in this case = spurious uninvited emails from companies other than Apple). One email was from a company promising to solve my erectile dysfunction, then the other one some days later was from an organisation advertising out-of-marriage relationships for the matrimonially bored. (I suppose at least the subjects were kind of linked.)
Now considering I've never ever used this account, let alone shared it with anyone, it's pretty clear to me who has divulged my details. Either that or the iCloud mail-severs have ben hacked (but Apple would never admit to a major security breach like that would they…)