For 3 years that i used paypal way back before,i will say that Its not a scam ,cause i have not encounteted one to say that paypal is a scam. Paypal is the most secure online bank before till i met bitcoin.
as long as I use paypal. I've never harmed because the paypal. I actually find it helpful to paypal because it can do shopping easily. if you feel cheated by paypal, whenever you can make contact support