I think most of this comes as a result of the following:

1. A large percentage of the population generally does not trust banks. A lot of people don't even understand that a merchant pays a % of every transaction they swipe, so they don't get where the money would come from. Their instincts tell them that the bank has to be profiting off of you somewhere and you just don't realize you're getting hosed. I don't even bring up miles and points, or banks in general to these people usually. It is a waste of time.

2. Many people don't think 1-2% or even 3% is more than some pocket change. They don't really care to think about finances more than they have to and figure this is just a waste of time.

3. If you mention manufactured spend (something I have only done a few times when some really really good deals came around), most people get uncomfortable and just shut down/stop listening, which I completely understand.

4. A lot of people don't understand and/or fear damaging their credit scores for those who are promoting churning credit cards. This is understandable. There isn't a published formula on the websites of the big 3 reporting agencies that says "if you apply for this credit card, your score will go up or down x points". A lot of people don't want to "gamble" with that.

I'm fortunate that I have a lot of business spend that allows me to accumulate a ton of points. People usually get interested in what I have going on because I will say things to the effect of "Bank of America paid for my hotel and airfare" or "I opted to rent the Mercedes since I wasn't paying for it anyway". I usually have the person chomping at the bit for more information when I explain it that way.

Best of luck to you. I've managed to get a few friends to pick up a great rewards card and put monthly expenses on it (think phone bills, insurance, etc). Hopefully before you tell anyone about these things, you tell them the same thing I do before I even start: You must always pay off the card in full every month, no matter what. I usually repeat this a few times to emphasize how important it is.