Could be a faulty alternator, alarm system, or radio, all of
which are generally connected to the unswitched battery feed.
The alarm system for obvious reasons, the radio often to
retain the station memory, and the alternator because it's
not practical or desirable to fit a high current relay, you
would blow all the cars electrics if you lift the battery
connection while the cars running, it's called a load dump.

With a 50AH battery I make that 333 hours (13.8 days) to flat battery.  In
normal use you would not notice assuming you use the car at least one a
week.  Even after two weeks the car would probably start Ok.  All this
assumes that the battery is in good condition.  If not then whether it is
100mA or 150mA you will have potential problems.

As for what is normal for a Punto I don't actually know.

Nick /////

Dave,

I had a simular problem with my Punto.
It appeared to be the removable front of the radio that discharged the
battery after 5 days.
(smal battery in that front is for memory of stations, when smal battery is
broken,
memory takes power of main battery )
When I didn't use my Punto for more than a few days, I removed the front of
the radio,
and than it would start.

Nico