Does it? I've only been to Portugal a couple times (Lisbon and Porto) and houses had bidets (standalone), while bathrooms didn't, but didn't have tp buckets either.
Depends on the age of the building and the locations seeer system. Newer sewers and buildings can cope but older ones can’t.
Then there’s cultural expectations - if you have a country where you have gone decades of your life never flushing you will be expecting a bin even if the pipes don’t need one.
If you are staying in western hotels in major cities you will have a different experience than staying in private homes in villages.