It is clearly a measure created to prevent tax evasion, which in Portugal is a real issue (as in most Southern Europe countries, I'm Italian) http://www.theportugalnews.com/news/may-2016-portugal-named-....
Since, as your parent says, in Portugal cashless systems are convenient are efficient, I don't really see the issue, aside from your personal preference.
It is clearly a measure created to prevent tax evasion, """
this shows the extent to which the banking system has brainwashed us, when 2 people cant conduct a large transaction directly without an intermediary and it seeming 'suspicious'
If you lived in a country where every other week you see in the news some politician caught on camera while pocketing corruption money, you probably would have another viewpoint.
You'd think.
I bought a house in Japan and I had to pay my deposit in cash, approximately US$10,000. Walking around with that much money, I've never been more paranoid in my life.
http://www.kalzumeus.com/2014/11/07/doing-business-in-japan/