when did this happen

Exactly at what time did it become the done thing to go to the toilet indoors? when did pissing and shitting outdoors ever become unacceptable?, why do we have special rooms in our house with with little watery waste wells, i mean nowadays if you came across soemone who still had a outdoor toilet the many snobs among us would say "oooohh noo how dreadful this chap must be he does it outdoors how awfully prehistoric phwaa phwaa phwaa", and id agree, i mean there is absolutely nothing unevolved about going into the corner of your house and letting your guts out is there shitting and pissing in confined spaces is healthy practice