Since its early days and until relatively recently, Google has had restrictions on various activities that a business might want to advertise or to appear in search results. Those included gambling.
However, as anyone who does SEO knows, the changing results from Google's algorithm updates have generally left people in the dark about what really matters in getting a high search result ranking. Some perfectly legitimate and 'nice' businesses have found themselves near the top one year and several pages down the next, courtesy of an update.
Just for a moment, put yourself in the position of a stressed out business, trying to gain ranking and imagine you went to a psychologist to describe the symptoms...
Psychologist:"Let me know a bit about your symptoms;- I don't need to know what you are actually doing, just how you feel"
Patient: "Well first of all, I keep doing things which sometimes seem to get a result and then next time I do them, they don't. So I'm getting really stressed."
Psychologist:"Do you ever manage to repeat the same thing and succeed ?"
Psychologist:"Could you eliminate the failures by changing your behaviour ?"
Patient:"Are you implying that I'm deliberately sabotaging my chances ?"
Psychologist:"No, not at all. I'm just wondering if there's a pattern ?"
Patient:"Its out of my control"
Psychologist:"What makes you say that ?"
Patient:"Nobody will tell me the rules for success"
Psychologist:"How do you measure your own success ?"
Patient:"By how much money I make"
Psychologist:"Perhaps you could enjoy success in another way"
Patient:"Its my income for goodness sake"
Psychologist:"Sorry, I wasn't aware of that. Perhaps you could earn more reliably if you got a job"
Patient (angry):"WTF do you mean ? It is a proper job"
Psychologist:"What makes you believe gambling is a proper job ?"
Patient:"Eh ? I'm not gambling."
Psychologist:"Well, you may feel that you can control it, but you said earlier that you felt out of control"
Patient:"I'm not gambling for goodness sake, I'm trying to get better search results"
Psychologist:"When did the problem first start ?"
Patient:"Its been going on for years. I blame Google"
Psychologist:"Its easy to attribute blame to others, I think we need to meet again quite frequently; you may have quite a serious addiction."
Patient:"Did you know that your psychology practice was on page 1 last month and now its dropped to page 5 ?"
Psychologist (turning on PC in a panic...) "WHAT ???"