Well, I don't know if he is a scammer or not but you can either keep your cool and asking for replacements or lose your cool and start this juvenile megabig-font crusade with urgency as if there was no tomorrow. But you can't do the latter and expect that the former will still work, if I was the seller and you behaved this way I would cut you off as well.

If you buy something in the store, it doesn't work, you go back to claim the replacement, they maybe don't react the way you expected, and you start acting out and offending people then they will simply call the security (and possibly even the police) and kick you out of there (and possibly file a criminal complaint against you for a verbal attack, threatening, whatever), regardless of the fact that you were originally in your right. Then, after you sort out your newly acquired criminal fame, you can file a rightful civil lawsuit against the store but then if you say one single bad word in front of the judge he will have you arrested for contempt of court, reject your claim and fine you in such an amount that you will regret not keeping your mouth shut. All the while your original claim about a non-working product bought in the story was justified.