There are people like that. You hear about their new partners all the time and see them constantly looking for new partners. That's not because poly is like that, but because these are the same people who would be serially monogamous if they wanted monogamy.

For me, monogamy just felt too restrictive. My wife and I both broke up with people who wanted monogamy not long before meeting and have always been poly. As a 22 year old I loved the idea of sex, but nearing 30 I love that I can have multiple happy and long term relationships. I love the fact that I could fall in love with someone new without risking losing my wife who I love dearly and cherish. And yeah I’ve been in two happy relationships for about 5 years now. And both my partners like each other and I like my girlfriend’s husband